The prequels are 100% garbage. Not sure why people point to them as anything other.
Well, maybe this, which came up in a discussion the other day with someone: this movie (TFA) feels "small" in comparison to the original trilogy, and even the prequels. It doesn't really feel like a grand, galaxy spanning adventure. I know this is a minor quibble, but the starkiller blast that everyone sees from planetside would mean that the planets blown up were in the same system as the planet Maz's cantina is on.
Anyway, that's a specific nitpick, but his point was that it doesn't seem like a galaxy romping adventure. Everything happens very quickly and without much sense of scale. I feel those are valid criticisms. Pointing to the prequels to make that point, though...