Keep in mind that you're 17, and these men are acting like children.
From their point of view, I can understand what they're getting at. Braids, imo, and on myself, can often make a woman appear younger, and more child-like. Perhaps that's what they were trying to, ignorantly, get at. Maybe with braids you look more innocent, and young.
However, are they right in that braids can't be sexy, hot or attractive? Hell no.
They have no right to talk to you as if your looks are for their benefit, and that you have to present yourself in a way that's pleasing to them. Ignore their ridiculous commentary.
You do not need long, flowing, silky hair to be hot, or attractive. It's a common, false, belief.
If you like wearing weaves, go for it. If you prefer braids, go for it. Ignore the commentary coming from immaturity and ignorance.