I have to disagree with you about Indigenous dress on two points.

I'm speaking to American Indigenous dress specifically because that's what I'm more familiar with but I'm assuming the same will apply to many other Indigenous cultures around the world. I just don't know the specifics.

First off, we've failes to distinguish between a clear mock up and one that's representative and more authentic looking. Some Indigenous cultures have special privileges for certain items that make up their traditional dress BECAUSE it's part of their culture. For example, it's illegal in the US to have in your possession the feathers or other body parts (like claws) of eagles and other birds of prey. If you're out hiking, camping, or hunting and you see an eagle feather in the ground, it's illegal for you to pick it up, keep it, display it, etc. But eagle feathers are an important part of ceremonial dress of Indigenous Americans and so they get a legal cultural pass. Those feathers also have to earned in many tribes. I'll also point out that Native Americans take great pride and great care with their traditional ceremonial dress. Even they do not wear significant festhers to the office.

So no. You cannot accurately replicate traditional dress and wear it just cause you feel like it. You very well could be breaking the law.

That's outside of just being a jerk. That's being a criminal jerk.

Secondly, even if your replica (cause you can't just go down to JC Penny and buy a traditional Native American dress) was clearly a mock up or you paid someone to make it....some of the materials are going to be sourced via illegal means. I'm thinking of something used more as a prop here, and White Sage is what specifically comes to mind. It's illegal to harvest except under certain circumstances. You can buy it in lots of places. That doesn't make it legal. Now you've gone and made yourself part of a criminal enterprise. Once again, this isn't just about being a jerk and people telling you off for being a jerk, you're a criminal jerk.

Just speculating here... I'd have to do some research and talk to some friends, but it's also possible that you might be okay with state or federal law yet still be in violation of tribal law if you pull that jerk bullshit on their land. Like I said, I'd have to research that. You wouldn't make fast friends, that's for sure and that's not wise in certain environments, like casinos. They own a whole lot of those.

Better to just not be a jerk in the first place.