You’re correct, most of America’s “grass roots” non-flying museums don’t run aircraft. Likewise North America doesn’t feature fast taxi runs which seem to be popular in the UK (for types the CAA won’t let fly).
Much of that has to do with the simple fact that the government doesn’t let “live” modern warbirds go into private hands. Hence, you won’t see a B-52 do fast taxi runs the way Vulcans and Victors are able to do in the UK.

And with so many B-17s (to give one example) flying, there is no urgent need for groups to spend their funds to get their static examples running as we see with Just Jane.

When you get into well funded “big name” group’s…CAF, Collings, Planes of Fame, the “Doc” B-29 group, Weeks, Paul Allen’s group, the lesser known groups that maintain and fly pre-war types (Old Rhinebeck, the Arango collection plus individual owners with flying OX-5s, Gnomes, Le Rhones, Hissos) I dare say North America could give the UK a run for its money.

Like many other areas, the nation’s warbird communities are as different as they are similar.