I thought I'd check this thread out to see what was to be defined as 'bad' music. Turns out that 'bad music' is the music most people in the world like! Does that make them bad people!
How do you cope with the fact that many of those people will be equally contemptuous and dismissive of the music people here love, and indeed call it worse names than 'bad'?
Oh, I know that one of the answers is in some of the commments above. We are right, and they are ignorant.
But what if they are right, and we are ignorant?

I can cope with the idea of a 'bad' song, although some people keep asking on Mudcat for lyrics etc for songs I consider thoroughly 'bad' - e'g' poorly written, banal, politically fascistic, grossly insulting, slipshod lyrics and lazy tunes, etc, etc.
Are they ignorant, or might we be talking about preferences and differences in taste here? If you blame it all on the power of marketing and feel it cannot be resisted, how come there is a Mudcat Cafe? Or are we the mighty and wise ones who see, but most regrettably cannot convey our knowledge to the masses?
How many songs on mass TV would it take to turn the millions on to the 'good' music. (By the way, classical musicians fell as superior to us as some of us seem to feel to the masses. But of course the 'serious' ones are wrong, and we are right - again.)