Another perspective to consider might be where tokens were/are created, i.e. the location of servers that mined the original tokens (or maybe the nationality of the owners of the accounts?) and the location of the witnesses that have added the coins to the ecosystem.
Yeah, I alluded to that in point #7. That's probably the strongest case for excluding STEEM from the list. But, a comparison case is Litecoin, which is included in the category. As with Steem witnesses, there's probably no way to tell where most LTC coins are produced at any given time, so I guess LTC was classified according to its founder.
Not sure if @officialcmc documented their inclusion criteria anywhere, but I haven't spent any time looking.
I wasn't thinking so much about the current witnesses, but more historically. I would guess that the bulk of the mined Steem and a lot of the early-witnessed Steem was done in the US.
There's probably no way to verify, but historically I think a lot of "witness statements" included info about where they claimed to be running servers.
True. Also, a substantial portion of new coins go to authors and curators. Before 2020 (in times of higher inflation rates), a large chunk of those rewards probably also went to US residents. I don't have the exact numbers handy, but I'd guess that somewhere around 75% of all tokens were created before 2020.