Certainly I don't think it's fair on the female gate staff to put them in the position of having to be the "sex police" (unfortunate term, there must be a better one - "bio bouncers"?) It would be awful and possibly dangerous for them. Not to mention super humiliating for any swimmers who are shy, androgenous or non-binary, and get challenged in this way.
It boils down to competing visions for the ponds. There are two ways they could comply with the SC judgement.
They could be seen as a pair of single-sex sanctuaries, spaces that are protected, albeit at a high price in terms of intrusive security.
Or they could have an open-door policy of "all who want to swim here are welcome".
Personally I prefer the latter. You don't, fine; most other pond users don't, fine; the Corporation doesn't, fine. So it will honestly never happen. Which means it's pretty pointless you all having a go at me. I'm not going to change my mind (this is MN; no one ever does) and my vision will never come to pass anyway.