Different anon, but regarding the number of universes dropping to 24 in Hickman's Avengers: Reed says in New Avengers #29 that there were hundreds of thousands of universes still around, but "something happened" and now there are less than two dozen. I don't wish to be contrary, but that does sound different than the natural attrition that you're describing.

Anonymous
Well, you may very well be right. Keep reading…