You think there is something wrong with being naked around your own children?
There are plenty of changing room options that allow for trans people to have dignity and also allow you to protect your children from ever seeing a naked human if you so wish. It doesn't have to be one or the other...
I think it is neither necessary or appropriate, is that ok?
On your second point, I never claimed it had to be one or the other but to appease both requirements you listed the solution can't obviously be unisex changing rooms then can it?
If there are individual cubicles for changing then great but that's not always available.