The way I see it, ActivityPub is the decentralised method we're paving the way for the distributed web.
People are educating themselves and with the fediverse having surpassed critical mass beyond the 1 million-user mark, it's now practically unstoppable.
In about a year from now we'll be seeing the beginning of the convergence between the decentralised-web, with the distributed-whatever that goes next.
It's not that those technologies are immature. It's that they haven't converged yet.