They were much more likeable before Durant, adding him tipped the scales too far in their direction. They were already amazing, but then became almost unbeatable.
And since the Warriors don’t appear to be breaking up their core anytime in the foreseeable future, it would do the NBA some good for a couple more superteams to form that could challenge and dethrone them. It sucks for the small markets that lose players in that process, but unless stars team up the Warriors will likely win something like 4 of the next 5 championships.