Forgive my FUD, but I'm bored .....
Think about it, most of these mining companies and mining pools are KYCd....all it takes is some pressure from daddy government to shut them down. And you gotta wonder why Intel isn't making chips for public sale anymore....is the government buying them up in a private sale?
Imagine the government gets 90% of the hashrate, then turns it all off right after a difficulty adjustment. That would fuck everything up big time.
This is the only thing I can think of that could still kill Bitcoin.