Yeah it is stadium locales/stadium design (open air) that makes a difference. AFAIK, no NFL stadium requires all the players to be vaxxed. NBA now has multiple locales.
I think Peter King wrote about the "closeted vaxxers" in the NFL before the season started. Guys who said to the media "well, its a personal choice and I don't want to divulge that...." and we all assumed that meant they were not vaxxed. But apparently a fair amount of guys did get vaxxed and didn't want to admit it to their anti-vax wife/parents/family/friends. We don't really know as the public.
NBA guys won't have that option. If Wiggins doesn't suit up at home at all, it will be obvious why.