The aggressive scruffing is bothering me too... And at the beginning when the cat is running away, he's got airplane ears going and he doesn't look happy.

I pet my cat's belly kinda like this, though I never grab the scruff. They'll scratch and bite you, sure, but it's never hard enough to actually be dangerous; they understand that it's play time. You just get used to having a few small scrapes on your arm most of the time.

Yeah, op post is just animal cruelty

As someone who rough-houses with their cat: No, dude. No. This is just playtime, a lot of cats love that shit and know that playtime and claws don’t mix, so they don’t do it because even stupid cats aren’t often that dumb. You can also trim their claws normally, like you should be doing anyway.

My cat is fully obsessed with me, is currently asleep on my lap, and when playtime comes around will be basically asking me to do this. He will easily switch back to chill mode after, even if it’s me who decides we’re done, and will be back to normal for bedtime.

You’ve either got no experience with cats or have only interacted with cats you’ve thoroughly pissed off because you can’t read their very clear body language.