Yes, it's got critical mass.

I haven't looked at Telegram's blockchain thing yet, but the non-blockchain version is not very private (and the same applies to Signal).

xx Messenger (https://elixxir.io/; source https://git.xx.network/elixxir/) has very solid encryption, metadata protection and decentralized gateways. But it's less polished, blockchain-based, and has few users.

People complain about the use of blockchain in messengers, but they offer no solutions on how to address app sustainability or eliminate metadata centralization, censorship, or risk of having your data handed to the government by the organization running the network. We'll see how sustainable your centralized donation-ware is.

Btw somebody mentioned "only" 1:1 encrypted chats: who does it better?

xx Messenger can do group chats but you can't add people to a chat after the group has been created.