Of course people make assumptions based on how you present yourself and how you look.
Sometimes this is unfair at every level ie statistically not backed up by evidence, for example thinking that someone with blond hair must have a low IQ.
Sometimes it is fair on a population level but unfair to the individual, typically where the feature leading to judgment is not controllable, such as my tendency to be more cautious around unknown men than women because I perceive men more likely to be a threat. Statistically valid, but I understand why it can feel hurtful to individual men who wish me no harm.
Sometimes it’s fair at the population and individual level because it’s an entirely controllable feature that is also statistically correlated with some character trait (even if in a particular instance the character trait is not present), for example thinking that a person who consistently dresses very provocatively probably doesn’t hold conservative religious beliefs.
If you dress in a way that consistently causes people to make assumptions about you, either accept that’s just how it is and ignore it, or change the way you dress. I dress quite boring and conservative, people assume I’m a bit boring and conservative 🤷♀️. If you happen to look a way that causes assumptions but it’s something out of your control then your frustration is much more understandable.
Obviously there’s no personal presentation that justifies violence, harassment, lack of basic respect etc.