In article , jacobnavia
writes:

This invisible mass can't explain the sorely needed black matter?

No, since it would mean a baryonic density higher than that obtained by
other arguments.

Yes, of course that would mean a higher baryon density... Black holes
and small cool white dwarfs are undetectable by most scopes.

But that kills it right there, since we have a very good idea what the
baryon density is, and know that most "dark matter" must be
non-baryonic.

Also, such a population would be detectable via
microlensing.

Sure, but do we have clear data in that direction?

Many microlensing searches were specifically designed to detect dark
matter (which could be in primordial black holes, for example), so
directions were targeted where one expects dark matter to be. Most of
the dark matter cannot be in compact objects over quite a large mass
range, though low values (mass of the Moon or less) and high values (a
few hundred solar masses) are not ruled out, at least if there is a
reasonably broad distribution of masses (which one would expect anyway,
as opposed to a delta function).

Normal stuff, what I think you call "baryonic". Yes, I would say the
normal stuff density could be much higher than what we think.

No, it can't. Read up on "constraints from big-bang nucleosynthesis".