From my understanding, it's still not "shared" in the sense that for a regular reader, it will still be a bonus that is paid from Medium's secret stash and not for the reader's membership.

It's now closer to the 50 claps as I understand. As in, if you clap 50 for everybody, then it's not a signal for the algorithm. But if someone usually claps 1 and suddenly claps 50 for one article, it's a signal this article is exceptional.