Liam, without meaning to, has summed up the problem.

Women are only losing rights of you use the boring old definition of "females": if you include all the people with penises getting lots of shiny new rights, then "women" are just fine.

Note who loses and who wins... https://twitter.com/elleandback/status/1252545438898667521

The serious point here is that females stand to lose language and definitions which enable our political representation. Women as a social and political class could be erased in law.

Comments like those of Liam & John Nicolson in this thread show this is very deliberate.