Metal isn't for everybody. Just because you dislike it doesn't make a genre (An underrated genre at that), shitty, though it's just an opinion of mine just like what you said is an opinion.
Metal isn't a disgrace to music, though. Compare it to techno. At least you have to learn instruments to play metal, such as learning a guitar to its full potential, learn to drum to its full potential, and, believe it or not, the growling vocals (Not screamo, screamo is shit punk), takes generally a lot of skill to pull off, some would argue more skill than clean singing (Though skill doesn't always equal it being good.)
Not for everybody, I understand, but a lot of the world is blind about metal because of the media, mainly.
Not trying to convince you or anything, but a lot of people who dislike extreme metal (Metal with growling), like this band below, Sigh, if that helps.
(Avantgarde jazzy black metal.)
Ecstatic Transformation - YouTube