I mean the obvious solution to that first problem is that you shouldn't be throwing out unsafe options when you're standing at exactly the right range for lslice to hit you. The area that lslice threatens isn't actually that large, and if you're standing within the very small portion of that area where it can hit on the first active frame, literally just dashing forward will keep you from getting hit.
This misses the point I was making. If you attempt to block, dodge, dash, or out maneuver lightning slice, you are at serious risk of being either punish comboed back into it anyways or being set up for something like mid screen lasso which just got buffed massively. The threat of the move is still pretty menacing, so you can't risk not taking some sort of evasive maneuver. But if the cowboy player has a brain, they'll either do something just as bad to you in response or worse if they believe you'll take evasive maneuvers. Now, this used to be worse back before the move got additional recovery. And isn't as big a deal now, but since Cowboy doesn't really use either of his meters for much, he can often whiff cancel on reaction to a block. Which, is honestly at least conceptually perfectly fine. Way better than him just being able to do whatever after a block for free.
Also it seems weird to complain about this but not mana strike, considering mana strike can pose exactly that same threat, but Wizard can also move it across an entire range of distances and it's actually faster than lslice (try pitting them against each other in single player)
Few things to note here. For one, I don't see people using mana strike that often tbh. Secondly, it can't be chained nearly as much. DI has way more of an effect on mana strike. Especially because it's mostly used on airborne opponents for a little bit of air chaining. I find that DI is much more effective in air combo situations. Thirdly, mana strike is usually just a means to an end, a hit for the sake of setting up something else. Rather than it just being chained a billion times. Not that it can or ever could be chained like that. Hence why I ain't got anything against it. This makes it like, infinitely less annoying. Mana strike is proof that lightning slice isn't inherently dumb. But it's misplaced being the way it is on cowboy's kit. Wizard also has a harder time giving you trouble for blocking it. And doesn't have much in terms of means to punish rolls so long as you aren't rolling into point blank range. Which, makes it a bit harder to punish than Cowboy theoretically I will admit. Since if the cowboy is silly enough to actually go through with the lightning slice while you are on the ground and you read it well with a roll, you usually get a punish. Not so much with Wizard. But besides that, mana strike is way less annoying than lightning slice.
Yes, if you're standing at one extremely specific range in neutral, lslice is a strong threat. You can also just not stand in that extremely specific spot. And in that spot, none of his other moves are a threat.
Lasso, gun, teleport with or without 1000 cuts is scary at that range, and unexpected forward dashes into something like thrust can put you in a dangerous situation. I'd argue not only is lightning slice dangerous for the sake of lightning slice I'd say it's just very slightly outside of the range cowboy would optimally want you to be in. If you get hit by the inner most side of the hitbox, a cowboy player can often teleport behind or in front of you and start an actual combo using other moves. Which, frankly, I'm ok with. If there was a way to make it so that's how the move was used and further crippled it's use in chains, I'd totally take it. That'd actually be cool and fun while still keeping the mid screen threat to society aspect of the move.
If you're pointing DI away from the cowboy, the lslice loop should be broken after like the second or third hit. They can teleport after you, but if they try to keep using lslice they will very quickly get to the point where you can just DI up or away out of range. Also teleport uses an air option so cowboy can in fact not just keep teleporting and chaining mid-air forever.
I never claimed that cowboy could chain it forever, and in fact I've noted multiple times that DI is the only way to escape, because you aren't in range for a burst hit. But I must restate this very important fact you have chosen to omit. Horizontal DI against this move may as well do nothing. Go ahead, try chaining it in training mode and have the other character do a straight backwards DI. It does all but nothing. You pretty much need to do straight up DI to get into the air, and then you can do diagonal up DI. But by the time that happens, the cowboy will be able to chain you no less than 4 times, if not 5 or 6 times. Before having to start another chain in the air. It used to be much more painful in fairness. Before 3.4 it was more like 8 reps per chain. That was a nightmare. It's better now, but I still hope to see the move reworked alongside buffing cowboy's other, actually fun and cool stuff.
Yes, lslice is a solid move that fills a niche in Cowboy's moveset. But to be honest you are making it out to be a way stronger option that it actually is. A good cowboy player is not going to be using it "every chance that they get" or even relying the threat of it in most circumstances. It comes out fast, but again it has a very specific range where it can hit someone even if they try to move and before they get to take a turn if they hold, and even then both the Wizard and Ninja have effective ways to avoid it safely.
Like Ninja for instance can just backsway at that range and unless the Cowboy just straight up hard reads the backsway specifically and commits to a move that will lose to most of Ninja's other options, they can't really punish it, while being hugely minus if they actually try to lslice. And of course Wizard can just mana strike, and that's assuming that their setups aren't protecting them to begin with (same case for Ninja actually).
lslice is just simply not an even remotely good enough move to carry a bad player unless their opponent is also a bad player that isn't even considering that the move exists. Lslice looping is also frankly just bad if the opponent DIs correctly, it quickly builds up a lot of knockback and does pretty sub-optimal damage.
Outside of the DI situation being misleading at best, this is fair. I'll give you the fact that the move is much, much, much less miserable to deal with now. It's been getting better nearly every update. But you must note, most of my statements were made back when the move was frankly completely bonkers. You seem to have a pension for omitting key context like this in your statements. For one I never said lightning slice ever carried bad players. I've lost to two cowboys ever, one wasn't using it, and the other was after the 3.4 update when the move got nurtured. What I suggested came to pass, and it's made the situation, at the very least mildly better. Lightning slice got slapped into submission, and other stuff was made more usable. Remaining cowboy players are actually making decent use of more of his kit now. This is good! (But it's returned cowboy to being pretty underpowered. More stuff could use buffs I imagine) Lightning strike at this point is really at it's best as a sort of looming threat that gives me and other players PTSD, bating us into rolling. Which, meh. I think the play these days is a backroll or jump over the hitbox if you have the advantage to do so. Like I said it's better now. It used to be better than mana strike, but now it's just about a bit worse in a vacuum. And in the grand scheme of things though it really doesn't have that much of a use on cowboy now that it's not his main grounded combo rout. So it's not much better in that regard now is it. So yes, lightning strike is in a much better state. But mana strike does not and never has made me want to dropkick a small dog. I cannot say the same for lightning strike.
In conclusion I'd say it's reign of terror is over. But of course, it remains annoying as per it's nature. Or perhaps I've just been psychologically primed to go hollow whenever I see it lmao.