Not sure if that list is comprehensive. Neither Ludovic Courtes or John Wiegley are on it (and they are both signatories of the open letter).
(Which, hey, speaking of RMS driving off contributors...)
Anyway, he hasn't done much in Emacs development for years now, I think. As a maintainer, his actual tenure was very brief.
Eli Zaretskii is the acting maintainer now.