Modern locker rooms can be built with individual stalls so I understand the point being made. Personally though, it's less efficient to have a locker room with multiple single-serve rooms. Extra material, extra cost, decreased functional area, additional readying time. If you use a locker room frequently you know how invaluable all those things are.
So my work did something like this when they moved buildings. Our old locker room was a long rectangular room with lockers on one side, a bench on the other. No privacy once you were in that space.
New one is mixed usage private change rooms and showers. It's a huge, huge, huge downgrade on the space. So, anecdotally, not on board. The old one still had bathroom stalls and private bathrooms if you needed it. I don't understand the push to make it all uniform when that's not the best use for the majority of the users. I'm not sorry about this opinion.
Not when you only need one large area rather than 2. Building double the showers and a shared area should be more efficient than having 2 sets of half for each gender.
It also makes it easier for families, non binary or trans people.