Hi!
The first day I got a steam account(last year), I spent 8 hours playing games. I was eventually able to get it down to 6 hours, and eventually to 5, but 5 hours is a lot of time to be spending playing something as not-worthwhile as a video game.
Over the next 7 months, I continued to have this addiction to gaming, barely paying attention to schoolwork and extra-curricular stuff. In December, I deleted my steam account.
I'm not a designer or anything but something about Steam's design makes the user more likely to spend a lot of time playing games and buy games. Itch.io doesn't really do that for me. I play about 30 minutes to an hour a day, mostly free game jam games, and I've been able to do a whole lot more with my life now. Itch.io is the only platform I use, and it doesn't really have the addictive-factor that steam does.
I guess it's just my opinion, but video games aren't a great use of much more than an hour or two. Sure, they're fun, but most games you play will leave your mind a month after you play them.
I hope that explains everything. Muck really isn't that big of a deal, it kinda just looks like another game that's famous just because of the developer behind it.