I have a theory, and it's not a Hybrid one.
Linkin Park wasn't hated because it was formulaic. A lot of bands are formulaic.
All AC/DC songs sound the same and they're still popular as fuck. So it's not that.
It's because they were popular with the girls.
All bands, regardless they are (or were) good or not, that were popular with the chicks always got flack:
- Skid Row
- Bon Jovi
- Aerosmith
- Nickelback
- Silverchair
- My Chemical Romance
The list goes on and on.
I remember Sebastian Bach from Skid Row was booed off stage here in Brazil and called Sebastian Barbie just because he was a good looking guy. The idiots did not respect him. Even Though Slave to the Grind is one of the best metal albums of the 90's (yes, metal, it's a killer metal record) - they started softer and went harder with that album, and still, they were ridiculed.
Silverchair as well... Daniel Johns was talented as fuck (later he went on to become a sort of failed Justing Timberlake in the 2010's, but that's beside the point). A lot of dudes hated the band just because girls loved him because he looked good. And the motherfucker was insanely talented with several great songs and Diorama was borderline prog-rock/metal at some points, but fuck him, he looks like a model.
Linkin Park, to me, because of their star appeal, went on to be ridiculed, but they had some great songs and Chester was a HELL of a vocalist. One of the greatest mainstream vocalists ever. I'm not the biggest fan of the band. I don't like all of their phases, I think I enjoy a good 50% of what they did, but they're undeniably good (at least to me).