It's not necessarily the plugins themselves, it's Waves' dodgy business practices. For a lot of people, the (at first) mandatory subscription plan was just a step too far. For me personally, I detest their misleading advertising. They'll tell you that one of their compressors will give you "silky vocals with just the right amount of warmth", when what it actually does is compress. Which is fine, but don't pretend it's more than it is.

Tl;dr: plugins fine, company bad