"treated as their sex assigned at birth" means everywhere. Not just sports teams, not just toilets.
It's medical access, it's workplaces, it's everywhere.
So you can now be denied access to medical groups or support because it's deemed single sex at birth, your workplace has to make accomodations and provide a gender neutral alternative toilet, many places can't afford this...so employment becomes an issue....it goes on and on.
The big problem is interpretation. Cos of the possibility of being sued, many places are going to be very conservative about allowing access and are going to be transphobic by proxy. Frightened into being bigoted like the Girl Scouts by lawsuits they can't afford.
Amnesty is just the start. It will take trans folks suing to get rights back, I fear. And of course JKR and co. have very big pockets.
So the effective laws of this nation is decided by the Epstein Class who don't even live here having lots of money.
Something everyone should be worried by, because who is next?