Right now it's kinda shocking to know that babies exactly made no main appearance in home console titles. At this point, common people still remember them via the recently shut down Doctor World, the topselling Kart titles, and additionally the cameos from the 2023 animation movie
I think the weird part about their isolation is, babies do have own solid fanbase support, and seem to be a irreplaceable part of spin-off rosters. Their major advantage is to make up for the main cast which mainly consists of grown-ups (not counting other non-human species whose age are hard to tell).
Aside from visual diversity, Mario game is the number one family-friendly gaming brand, so I assume many family gaming occasions would still require underage characters to appear in the selection screen.
Altho Mario babies do have a major defect: their alterego status makes spin-off rosters less diverse, the other problem is we don't really see Nintendo try to push other original underage characters, like 9-volt, as reasonable replacement for the babies. So the recent rosters basically dissapoint both sides of the fans.
I mean even if we don't want babies to participate in very violent subject like football, party would definitely be a fun occasion to have babies and now we've got over ten Mario Party titles with zero playable babies.
Right now it feels like most spin-off subjects are done on Nintendo Switch. Unless Nintendo surprisingly annoucne new DLCs, babies are likely doomed in the current console era. We might get a new Baseball title but babies also have participated in this subject before.
As for mainline, we've also not seen Yoshi title focus on babies in gameplay for a while. It especially embarasses Baby Daisy who was forced to debut in a spinoff decade ago, yet she's not got any major chance to shine.
I don't think the chance is high, but I think it's acceptible to have a second Yoshi title on NS as long as it gives more focus on babies.