99% of FB's moderation has nothing to do with "biases", unless you think FB is biased against spam, scams, and all the other dregs of the internet that incessantly pops up anywhere users can post content.
Quite a few people left Threads for Bluesky because progressive posts were being removed while far-right, antivax, etc content was allowed to stand even though it was reported.
At best the algo is imperfect. At worst it really does seem oddly selective.
I am a humble Cialis salesman, like my father and grandfather before me. I confirm Facebook is biased against our profession. (My grandfather also moonlighted as a Barrister representing the estates of deceased African royalty—it was always so difficult to track down their heirs.)