That’s where your understanding is wrong - nobody is saying that dark matter can’t be microscopic black holes. There are reasons to assume this to be untrue (e.g. microscopic black holes evaporating incredibly fast), but “dark matter” is a placeholder for whatever the underlying physical phenomenon is, be it microscopic black holes, or WIMPs, or whatever else. You yourself are asking for your explanation not to be considered.
That’s where your understanding is wrong - nobody is saying that dark matter can’t be microscopic black holes. There are reasons to assume this to be untrue (e.g. microscopic black holes evaporating incredibly fast), but “dark matter” is a placeholder for whatever the underlying physical phenomenon is, be it microscopic black holes, or WIMPs, or whatever else. You yourself are asking for your explanation not to be considered.