We had an old Apple TV HD (that is, the model before the Apple TV 4K - specifically, A1625). We tried to use it with a new TV, but we had to replace it with a new 4K because we noticed that when playing back shows either live or recorded from the ATSC3 version of the local Fox affiliate (WJBK) they look like they're in sort of stuttery slow motion.
I guess 7 years is a long time...?