The music detection stuff I feel was probably bigger than them. DMCA and whatnot. You forget YouTube follows suite in this regard.

Not keeping videos forever honestly made sense to me. They were very scientific about it in their blog post and showed that honestly, nobody is really watching these archives. If at most they're there to watch a certain clip (which can be highlighted which ARE kept forever).

Banning cleavages again makes sense... Otherwise the site would turn into a softcore cam site with gamers.

I'm not saying you're wrong; Twitch can certainly go down that route, but most of your examples are in my opinion exaggerated.