The music metadata situation is pretty bad, but the source of the problem is not really carelessness or greed or avoidance of responsibility (although those are all true). The true source of music metadata complication is the insanely complex copyright regime that music operates under. It's a legacy codebase about a century in the making that is constantly being patched up by congress, mostly by trying to change who is being protected from whom. (Among the folks favored at different times: labels, publishing companies, performing artists, song writing artists, radio stations, streaming music services, live venues, ...).
Perfect compliance with these laws is effectively impossible, so everyone is just doing the best they can. And any attempts congress makes to change how things work end up being gigantic legal battles because it's a zero-sum game and the more money in the "right" hands (e.g. these artists being ripped off) is less money in the other "right" hands (e.g. the unprofitable streaming service we all love).