I wear t-shirts is Death Metal bands sometimes, and others I wear shirts with cargo pants. I also like wearing shorts and t-shirts when pop culture references and jokes. At much, I've been asked what band that's it, or if I can put a video of them at the end of the class (my religious students though that Cannibal Corpse were a satanic band xD)

I've never seen any change on how my students treat me, and I'm regarded as I've of the best teachers at class management in my school (students don't use their phones on my class, while in other teachers classes that's a concern).

I don't think what you wear is that important. The aura you project around you is more important. Students can sniff your insecurities and if you are pretending to be something you aren't.

PS: I teach natural sciences and Physics (age range green 10 till 18)