Again, I agree. And I'm also a free-speech absolutist. Maybe where we're not quite communicating here is that I think the current climate makes it controversial (and socially and economically dangerous), to define "woman" in a way that it's been defined for thousands of years.
I think it's people like Ketanji Brown-Jackson and Keir Starmer and Anneliese Dodds, on and on, who are afraid to answer in a way that honours their sincerely held views, because answering in a way that, even ten years ago, would have been totally uncontroversial, is now immediately mischaracterised as bigotry.
Which brings me back to the original question; why make trans acceptance and solidarity conditional on the willingness to redefine the word "woman"? I don't think Keir Starmer or anybody else would stumble over the definition of "trans woman". I don't think, in a less politicised climate, they'd stumble over the definition of "woman."
As I said, it's not possible for a single definition to work perfectly in 100% of cases. But I don't think it's necessary either. Especially when it works in 99.98% of cases. It just seems like a really self-sabotaging battle to be fighting.