We should get rid of gis and belts all at once :
- makes BJJ unrealistic (tell me what you want, it does...) ;
- doesn't say that much about someone's level when belts are given by time and attendance ;
- strangles and chokes with a gi put you more at risk of larynx injuries as well as strokes (super rare but still happens, I remember it happening to one Sherbro, fortunately he made a good recovery) because of the fact the pressure you can apply with a gi (which acts like a rope) is way more than what the human body is supposed to handle ;
- ego things : low level black belt go full spazz when you are a blue belt their size they can't tap or even dominate. Btw, all the "white belt spazz" thing is complete BS : either you are someone who is chill and relaxed, who doesn't give a f about winning in the gym, who cares about his partner's safety as much as he cares about his own one, who wants to win via superior technique and tactics rather than strength and sheer aggressiveness, or you are a douche who is the exact opposite on all the abovementionned points. This has everything to do with personality and almost nothing to do with belt level.
I could give you countless examples of black belts who behave like shit and injure you everytime you roll with them (especially when they fell threatened of getting tapped by the blue belt) as well as countless examples of white belts who have a blameless way of rolling.
Bonus : gis take too much space in the laundry