But I think it depends on the reason for the "uniform", surely?
If it's because it's prescribed by some invisible societal expectation, they can get to fuck.
If it's because the clothing is just more practical/convenient/suitable for that particular lifestyle, then a "uniform" is probably more understandable.
For example, before I had my DC I was always in heels. Always. The higher the better. My DC are now 14 years old and have very significant SEN so I need to be mobile and able to dash around. I don't think I've worn proper heels in years! The mum uniform I used to see at the playground was shoes that let you dash after a mobile young child/toddler, trousers/leggings so you can easily get on the floor and play, and a warm coat for waiting for them to get out of school when it's absolutely bloody freezing! Why wouldn't you wear clothes that are suitable for your current lifestyle?!
Having said that, I bloody love a maxi dress and wear them all year round so often I look very different to most 😅
I will dress how I choose. Sometimes more for comfort, other times more for clothing that I love the look of. That might mean that sometimes I wear the so-called uniform - but it's coincidental and not because I'm trying to fit in with societal expectations.
If anything, if you deliberately choose to avoid clothing that you think is a uniform simply for that reason, then you're still being manipulated by what others expect of you!
Wear what you like and what makes you feel good, and fuck whether it means you're wearing a uniform.