So the concept of gender will probably stick and over time we will get used to categorising people by different types of self defined gender at least socially. The body modification will become less common as the roles become more everyday.
Then body modification is likely to become more common, not less. Because for many young people a change of "gender" appears to be a downhill pathway towards physical transition, a slope they slide down faster the further they go. It's one thing to let boys wear a frock or play with dolls or play with the girls while still confirming that they are boys and will grow up to be men. It's a whole other thing to allow them to believe they are, or can ever become, girls; to tell them they are now "she" not "he", they can use the girls' facilities and be treated as if they are "really" girls. (And vice versa for girls.)
Because telling young people (some of them - we still don't know how many!) that they can change their gender only increases their urge to become more and more like the other sex and to feel wretched because no matter what they do it's never enough. If they're lucky they come to that realisation before they have done massive physical damage to themselves. If they're not lucky, the realisation only comes afterwards.
Sometimes that's because changing "gender" was a grabbed "solution" to a different problem, a solution which gave temporary relief which young people then obsessively cling to, even while it fails to work in the longer run so they have to do more and more to achieve another temporary sense of relief. And sometimes because this "solution" was affirmed by the people they trusted and other solutions were dismissed. (e.g. listen the interview with Teiresias on the latest "Gender A Wider Lens" podcast 99 for an example of both - and this is a young man who went through the supposedly gold standard Dutch protocol.)
This is a huge stumbling block that trans activism will struggle to get over. Parents do care what happens to their children - even if some parents use the same "it wont happen to my family because..." magic thinking that other women apply to rape.
"Woman" may never return to a single sex group.
I hope it will. "Cis women" was one of the best moves trans activists ever made, and one of the most self-destructive for the women who use it. Define yourself out of existence. Smart women, foolish choices, eh?