I've always been a bit confused about the idea that an advanced civilization would be uninterested in us because we've "only" reached the ability to communicate via radio waves. We're either a threat or an ally to these other civilizations, and if you were them and you detected a society that was clearly on course to eventually catch up, it would be in your best interest to treat them like one of those things ASAP so you can have a hand in their development.

To me it feels most likely that our signals just have not had enough time to get to them.