Observations keep poking holes in those hypotheses (I’m not sure they even count as theories). We keep finding black holes with anomalous masses, or black holes that formed too early.
Part of the problem is that we have very little observational data. But another big problem is that our best ideas, based on general relativity are known to be incompatible with quantum mechanics.
Part of the problem is that we have very little observational data. But another big problem is that our best ideas, based on general relativity are known to be incompatible with quantum mechanics.