>a guy wearing leggings and shirt to the gym
A guy who stopped caring about the outside world's opinions. He truly became a wolf who does not care for opinion of sheep. He just wants comfort and performance with the added benefit of reducing laundry load. His life is about training, he is most likely above average to elite in his physical interest. He doesn't feel sexually turned on from wearing tights in public (or else he would be carrying a boner everyone could see). He truly is pure and an athlete at heart.

>a guy wearing shorts or sweats over leggings to the gym
A guy who wants the comfort and benefit of compressions during a workout but he is a pervert at heart and very insecure. He is afraid of opinions, thinks of a gym as a social place rather than a personal sanctuary to grow in. He might grow character eventually, but he is an insecure pervert at the moment.

>a guy wearing sweats or shorts to the gym
Either simply unaware or how amazing compressions are for workouts and performance, or just an insecure loser who wants to blend in to society's norms or a huge pervert who doesn't want attention so he can blend in and watch others. Way too much variety to say for sure, but they definitely are at a lower calibur than those who wear compressions alone.

>a girl wearing compressions to the gym
Slut bitch attention whore who just wants to show off her ass crack through see through leggings or wants to show off her ass to men so she can get her vagina wet from exhibitionism.

>a girl wearing shorts or sweats to the gym
Prude insecure bitch. Closeted self hating gender hating feminazi bitch.