This is an issue that’s really only made complicated by people competing to try to ensure that the concept accommodates their prejudices.
The simple reality is that the only way in which people are fixedly and simplistically one or the other is in the arrangement of their plumbing, and that’s really only relevant to things like a nurse charged with installing a catheter.
All the rest is an enormously complex combination of chemistry, environment, socialization and self-image that includes everything from the plumbing of one paired with full identification with that one to the plumbing of one with full identification with the other and includes every possible combination between the two, so insisting on absolutism is foolish at best.
I’ve been posting on internet forums for almost 30 years now. It’s just a thing I like doing.
I’m here now because it’s the best place I know of at the moment.