Another band that I listen to that are frowned upon is Five Finger Death Punch, both Korn and FFDP both were bands that helped get me into Metal so my opinion on the two might be far more lop sided. FFDP have only a few bad sides, for example some of their lyrics can be a bit idiotic and 'tough guy' but lyrics aren't what you look for most in music though is it? I think their vocalist Ivan Moody is one of the best Metal vocalists (check out his other work with Motorgrater and Ghost Machine too) I personally see FFDP as the next Metallica.
Their song 'Remember Everything' is very Nickleback-ish too which may make people look down on them.
Job For A Cowboy still sadly get looked down on for their earlier Deathcore work (which I thought wasn't that bad). They have a brilliant straight forward Death Metal sound now that is incredible.
Remember every thing I say is personal opinion and musical taste is subjective.