Considering that plenty of Americans march in the streets to show support it seems pretty clear that quite a lot of people care. Not saying that it will change anything in the election result, but it could very well be a step on the way, either to a comeback in 4 years, to some other Trumpish candidate or at the very least to another major participation in the Georgia runoffs. It's in no way impossible that Trump will pretty much disappear after leaving office, but it could also be just the other way.