Is it really over for crypto if Binance exchange or Tether go bankrupt like FTX?
No, people who don't lose most of their money (if Binance or Tether company went bankrupt) will just move on to different exchange, stable coin or pegged coin. You just need to see past collapse of centralized exchange or stable coin such as Mt. Gox or Luna.
Can crypto survive without the centralise organizations and projects?
Decentralized cryptocurrency or cryptocurrency which has supportive community (excluding those who only care about price/profit) will find ways to survive.