Given the last misplaced thread, I had to add another clarification on top of the page. After a discussion on #wikimedia-dev just now, I think a more correct synonym for the team's name would be "Central features", where central means that it's like a central square everebody goes through i.e. features affecting main/common workflows of (at least some subset of) wiki users. Right?
"Core" is wrong and confusing in so many ways. (Un)relatedly, I wish there was some team devoted to improving the most impactful features of core (like patrolling, recentchanges, diffs)... but that's definitely something this team does not and which is more likely to happen under "Platform" I suppose (if such distinctions even make sense).