serious if he wanted he could create a nostr client and transfer all the data of twitter to a relay then use that relay and other 2 or 3 relays to create acounts on nostr replace twitter x.com with that client and setup that when people logged on the client they would automatic log into nostr.

sure he would have alot of people private keys but then thats up to them if they want to change/create a private key that he wouldn't have access to it.