In article ,
"Robert L. Oldershaw" writes:

The recent LIGO events suggest that a significant fraction of the dark
matter could be in 10-30 solar-mass black holes.

I think that you would probably accuse anyone else extrapolating from
two events of being over-confident.

The 10--30 solar-mass range is not probed by microlensing so, yes, some
could be there.

MACHO results are
consistent with up to 20% of the dark matter in the form of black holes
in the 0.5 solar mass range.

Let's grant this. Still, most of the dark matter cannot be in objects
of mass which would show up in microlensing. So microlensing has not
detected "the" dark matter.

You seem to be unjustifiably dismissive of stellar-mass PBHs.

Because the observational constraints---as explained in detail in the
Carr et al. paper---are quite tight.

This is
especially inappropriate when there is so much uncertainty in our
current knowledge about the dark matter.

Let's not rush to absolute judgments.

I'm not. It is you who "knows" what the dark matter is and who rushes
to judgements about the significance of negative results. Again,
absence of evidence is not evidence of absence. One is, correctly, not
required to prove one's innocence in court.

While I see no reason why most or all dark matter can't be in PBHs as
long as the corresponding mass range does not conflict with
observations, it does look contrived if there is just enough room in
just those mass ranges which are not (yet) accessible observationally.
Sort of like of "God of the gaps" theology---technically possible, but
contrived.

With WIMPs as well, there are ranges of parameter space which are not
probed by experiments. Why is this a mark against WIMPs, and a mark for
PBHs?