I seriously don’t see how The Phantom Menace is more watchable than Revenge of the Sith. Nothing happens in TPM that we care about; and Jar Jar and TPM-Anakin’s acting are not more watchable than ROTS-Anakin’s acting.
It depends greatly on our own point of view. If you’re looking at it from the perspective of the overall story of the saga, sure it’s fairly superfluous. But taken in isolation, it’s a grand, impressive, and weird sci-fi movie that just happens to take place in the Star Wars universe where ROTS tries so much to tie into the OT that it can’t help but be lessened by the comparison.