Unless someone has beat me to it? Seemed like an animated discussion still going, if anyone wants to continue. I wanted to reply to Cautious Lurker who said it was for society to uphold the law and stop people going into the wrong facilities. My post (before the thread filled up) was going to be:
Well, may I nitpick - it's down to service providers and employers. They are the ones subject to this law. It's not "for us as a society" to ensure that individuals follow the rules that service providers and employers bring in so that those organisations may comply with the law. I'm all in favour of the law, but it's not on my shoulders to uphold and enforce it in every leisure centre and office block. We did all the hard work of campaigning and crowdfunding just to get the law itself clarified. I can now just use my voice to complain to the provider if my single-sex space turns out not to be. Because the law is on our side.