Thanks for the interesting link. Can’t argue with Sean Carroll. Except of course for the people who do argue with Sean Carroll. Ha ha. But that’s way above my pay grade. But some do argue, even in the comments on that linked blog post. Sean’s responses there are of course also excellent and worth reading.
Yeah! I think this kind of question will end up being a question of definition for future generation of cosmologists…
With the current definition, it seems the universe is not a black hole, but shares a lot of characteristics with them (except its singularity is in the past, but the future). If enough scientists like the idea of the universe being a black hole, they could simply modify the definition to allow “time-reversed black holes” as well, which seems to include the universe (if I understand correctly… My GR courses a far I’m my memory!)