Well, it all comes back to the question......WHAT is a woman?
If you define woman as ADULT HUMAN FEMALE, then how can a biological man ever be an adult human female? The answer obviously is, he can't.
If you define woman as some sort of ethereal, cloudy, non distinct feeling, then a man can be a woman, but he can also be a dog, a cat, or a hippo if he 'feels' like one, and if his 'feelings' are to be believed and indulged. Why is that any more silly than feeling like a woman?
HOW can a man feel like a woman if he has never been one and has no point of reference? Just because he may not feel like a traditional man or fit into masculine stereotypes, does not therefore mean that by default he is a woman.
Woman means female at a biological level.
We know it's impossible to ever change biological sex (and we've heard all the arguments - hormones can change, genitals can 'change' to an approximation of the chosen sex etc). It does not result in anything other than a natal man on synthetic cross sex hormones who may or may not have had body modification surgery to resemble a woman. If the hormones are stopped, his own natural body would reassert itself as fully male again.
Sex is binary.
Sex is determined genetically at CONCEPTION. We are not all "female" in utero (at about 6 weeks the SRY part of the Y Chromosome (if present) expresses itself and results in a male foetus all going well, if not, it may result in a DSD.
Sex is immutable.
Unchangeable.
And none of this is "transphobic" - facts cannot be transphobic. Facts are just facts. Facts don't care about 'feelings' or beliefs, or an internal ideology in some man's head.
The facts will still be the same in 100'000 years. That's how we know they are facts. Science books will not be re-written.
Yes you entitled to your own opinions.
But your are NOT entitled to your own facts.