Different cultures and different religious traditions have different norms, that’s the main thing. Giant religions, especially relatively decentralized ones are not a monolith.

In the Gulf states the all-black style is more common for locals, Saudi is massive so it’s different in some areas, here in Lebanon you have many sects and the all-black is more associated with fundamentalist Shia Islam, and so on. Most women who wear headscarves are wearing colorful ones.

As a little kid when we still had a bit more tourists coming from Kuwait and the UAE, I would see some women in Niqabs (full face cover) and metal face plates, which would freak me out. Those are not a thing here.

I think most Americans think all of these are one blob, and use “burka” as a catch-all. And that one is only a thing in super fundamentalist societies in places like Afghanistan, not something common at all. It would be like me assuming all Americans live like the FLDS.

If you are a woman in a heavily Muslim country I think the last thing you'd want to do is draw public attention to yourself

https://en.wikipedia.org/wiki/Hudud

The point of the hijab is effectively to not draw extra attention to yourself. Colors and patterns are pretty common in less strict countries though.

Slogans and logos are kind of problematic for somewhat similar reasons but companies like Adidas have been trying real hard for years to make it work. There's also a drive that Islamic things specifically should not follow western ideals, and that could be the most western thing we've ever done.

The same countries also ban music .... no fun allowed!

Modesty.

If you're living in one of those very conservative on women's dress Islamic nations (i.e. Middle East or Central Asia) then there are cultural limits imposed beyond the baseline of the religion.

A Senegalese Muslim woman in colourful patterned headscarf and matching dress is following what Islam requires.
Some places have kept, or imposed, much stricter controls on women's dress (amongst other things). And while they might choose to wear more colourful ones, many of these countries (i.e. Saudi Arabia, Iraq, Iran, Bahrain, through to Pakistan and Afghanistan) turn a blind eye to femicide and are plagued by honour killings.