It isn't that hard to get to a Sunday mass in the US said by CMRI, independent or Lefebrve line priest. A few rare places actually have old priests that were ordained in the old rite, before '72. Even the FSSP has some priests through the line of Abp. Lefebrve.
The people I know who can't get to mass in the US are usually very rural. Those I know who cannot get to mass in Europe tend to live in large cities. Not every European country has the traditional mass, either. If they do, it might not even be on a permanent or regular basis. From my observations most countries tend to have one good option, as in one strong, well-run mass center, for traditional mass within their borders, if they have it at all. There are exceptions.
I don't tend to count places where the so called "extraordinary form" is preformed. We all know those situations are temporary or just a stop gap to appease people, at best. If one did count those situations I still think the US would have the most.
There was serious tension between the US clergy and the progressive European clergy at the time of the V2. We had some real heroes here. I know the US gets painted as liberal, but Europe fell first.