It's my personal take on it, but I felt like the promise of the OSR was two folds: go back to a style of play which has some specific qualities over the more modern approach, use a common framework on which we can build and expand instead of reinventing the wheel constantly. What I seem to see in the several produces I've touched is exactly reinventing the wheel and very little creating new stuff on top of it. The same monsters come back in bestiary after bestiary, equipment lists that are almost identicals, slight variant on the same few rules; or sometimes the rules are exactly the same, but there's just a few different random tables sprinkled around.
If I go and spend 70$ on a big rulebook for a very different system from another publisher, I tend to find something quite different with at least a few interesting things to mull on.