They aren't complicated, just strict
The vast majority of the dialogue is for narrative purposes, not teaching (and on that note there's so much text, particularly late in the game, which either duplicates, appears earlier than it should, or appears after the thing it's discussing has already been done)
Again I didn't get to play the earlier iteration but i'm not sure how much harder (less room for error) the original could've had in the final fight? There's very minimal room to do it any quicker than I did I feel
I enjoy hard games, wouldn't want it dumbed down, just a small degree of leniency (small as in an error of what actions you could take- travel in/out of the wrong area once) not just 'hey you get another second, unsure what you can do with it, but there you go'
I know that's not the simplest thing to do
For the text being long idk, I feel like it adds depth to the story later on, as for it repeating or appearing when it should not, that is totally possible as the conditions system behind it is pretty bugged and should be fixed.
The final fight can be still done by taking a full hit from the sentry, maybe even 2, especially if fully mastered, idk if you are doing the best sequence of actions but to me it seems like there is quite a bit of leniency, but I can look into making it more forgiving