I feel like you may be talking about a nonstandard use of occam's razor.

It's the basis for a common use. However this seems pretty clearly wrong or incomplete.

I think the grandparent's argument really had more to do with "reason(ing) over limited information" vs frequencies in a possibly infinite space-time continuum. That still seems like a weak objection, given that anthropics look related to the topic of fixing Solomonoff induction.