TPM is, as I believe Ebert said, “a pretty good bad movie.”
I definitely enjoy the prequels (especially TPM) in the same way that I enjoy the campier Godzilla movies. I lower my expectations, and I end up getting to enjoy a corny space adventure, with fairly impressive effects for the time, and some intriguing ideas that I can appreciate more now as an adult.
A big part of why the prequels were so lambasted for so long is because people only had the OT to compare them to. By any metric, the prequels were a huge step down from their predecessors, so that made them look far worse than if they had been their own series. With the new batch of Star Wars films, there’s a new basis for comparison, and many people’s perspectives have shifted, since the prequels are (arguably) no longer the low point of the saga.