They do for NAGA No GI. I think the reasoning is that you will get wrestlers or sambo guys that have like 5 years of experience but are a white belt in jiu jitsu and they dont want them competing against a 5 month jiu jitsu white belt, ya know?
They do their GI division IBJJF style so that's belt based
They do their GI division IBJJF style so that's belt based