Beware thinking that environments where people don't dress formally are environments where people don't judge based on looks.

I don't love wearing a suit and tie, but do it for my day job. If I go to a tech meetup after work while still wearing my day-job clothes, I find a lot of people judge me to be someone not technically serious, based on how I happen to be dressed at that time. Prejudice based on appearance is a cognitive shortcut lots of people overuse.