You're thinking about this from the wrong direction. Parent is saying that not all 0x things are crypto (because it's the general signifier for hex), not that crypto people don't use 0x.
This was originally brought up in the context of saying that certain people removed eth and added 0x which is in context still clearly a reference to crypto, so the username fad just changed, and these probably (sadly) shouldn't be seen as Ethereum/crypto dying or losing popularity. Your implication is that Ethereum and crypto are dying and their users are en masse getting very interested in computer science and the hexadecimal numbering system and all happened to decide to change their names to include 0x for that reason, but it seems a lot more likely that the crypto cult is just playing follow the leader.
No it's not. Where did I say that?