When battling with the balancing of rights conundrum and the fact that rights are NOT a pie (duh), and that one side DOES have to give way to some degree, the way I think of it is sometimes like this...
If transwomen are accepted as women or female through their inclusion in any or all of the accommodations made for women due to our femaleness... women disappear. Our identity's degraded (downgraded!) to the point that we're left with no universal recognition of what we are / unique accommodations / unambiguous language to describe or name ourselves or our needs.
Whereas if transwomen are treated as a distinct class, we can recognise their identity and address their needs. They retain what women lose: an identity and a name of their own - and recognisable needs that they can name and advocate for.
Only one of these approaches gives both groups recognition.
Yes, it demands a compromise. But a compromise that still recognises trans women as what they are - what they actually call themselves - is a far cry from demanding such total self-sacrifice from women that we're subsumed into a homogenous mass of self-identification (with all that entails for a demographic still so under-represented, under-researched and under-protected - and dying in their millions because of this - globally).
It's not easy - of course, the very definition of trans women is wants-to-be-seen-as-woman.
But when you consider the implications of accepting this and the extraordinary numbers impacted as women cease to be a recognisable, protected political class (my other approach is a reluctantly utilitarian one)... it does honestly feel like something of a zero-sum game to me.
The other thing is...
The "transwomen are women" approach has been tried and isn't working. We can see it in the backlash trans individuals are now enduring, and the gradual loss of earlier "wins". All the time that supporters of this ideology were fighting their losing battle for trans inclusion in the class of "woman" - and as long as they continue to do so - precious time, money and effort is being lost (otherwise willing allies - me! - are being lost!) which could be far better expended in seeking more realistic, long-term solutions: third/fourth spaces for loos / adapting previously male categories to be "open" in sports etc.
And this would also lead to wider acceptance, better understanding and, frankly, less volatility and resentment all round.