I'm going to just point out that some women aren't comfortable in public changing rooms at all. And that some women used to felt uncomfortable changing in public changing rooms if there was a lesbian present. And some women would be perfectly comfortable changing in front of men. My point is that what people is comfortable with is a mix between your personal preferences and what has been normalized in our society. Now no one bat an eyelash if a lesbian is in a changing room, but they used to do that. Before people changed into private cabins, now most people do in the common area. And in hospitals they give you those ugly nightgowns that show the ass to everyone. XD

The point is, we could reach some point when no one would care if there is a woman with a penis changing beside you as long as she is clean and respectful. But if a woman oogles or touch inappropriately, it really doesn't matter if she has a penis or not. Or if she is just deciding if you have had a boobjob or are your real tits, she is being disrespectful.

In fact, chances are that the woman with a penis is the one who would be looked at of feel more uncomfortable. People would oogle because we are not used to. And they would be harshly criticized for things that we would be giving a pass to other women like leaving your towel in the bench and taking too many space.

So my suggestion is "common changing rooms with private cabins". Eventually people would just stop using the private cabins to change because they won't want to wait, but you'll keep your modesty if you want to.