@eric you are right, but that was not the point of the post. OP laments that all other keybase alternatives are based on blockchains, not keybase. And this is sadly true. I've looked into many alternatives and spoken with a bunch of them. All blockchain based.
The choice seems either centralization or blockchain.
And then, there is this small 1-person project named @keyoxide that does provide decentralization without blockchain 😅
Personal instance for myself.