It's true that good and bad music is subjective.
But man, some people go way too far by protecting AND hating musicians.
I am NOT proud of it, but i can name 5 messed up and not so great people, few are musicians, few are not. Messed up, why? They did inhumane things. I know more, but kinda forget them. Anyways...
Musicians can be great and bad people.
A good musician can be a horrible person. However, money and fame can sadly let you get away with murder and r1pe so, you can't be 100% sure. But even good musicians can be great people. Scatman John is amazing in my opinion, and i feel like Haddaway looks simple but cool as well.
And bad musicians can be decent people. But even bad musicians can be even worse people.
However though, people can go way too far with hating singers they don't like. Look at Justin Bieber, in 2009 to maybe 2014, he was constantly hated just because people didn't enjoy his music, though that isn't all, people even wanted to kill and r1pe him, compared him to Michael Jackson, Tupac, Freddie Mercury and made comics of dead and alive musicians insulting and mocking Justin Bieber. All because of his music. I don't know much about him, but man, he didn't deserve to have such insane haters. Like him or dislike him, there are people way worse than him but they do nothing about that. And didn't Rebecca Black get death threats just because she made a song, Friday that is also hated? (Youtube removed dislikes, but that song had more dislikes than likes)

Notice:
Just because someone makes good music doesn't always mean they're good people. Art is art. Artist is artist, a flawed person, but who really knows if they're guilty of horrible crimes or if they're a decent person.