I think a lot of these "worst songs/most hated songs" are based on received wisdom: the idea that you shouldn't like Ed Sheeran or Coldplay or whoever. And while it's true a lot of that stuff does nothing for me, I also find it really easy to ignore stuff I don't like because, in 2021 if you don't like something you don't have to endure it. Back when there was only the radio, a handful of music programmes on four channels and The Box which cost 75p per minute to call for a request, I couldn't escape things like Boyzone etc. But now - it's all at my fingertips between Youtube, Spotify and less legitimate sources. I don't need to listen to that stuff. When people rant about how awful something really boring is I find it very performative now: just don't bother with it and save yourself the hassle.
I also think a lot of this received wisdom is based on a hypothetical listener too. The idea that "Tesco mums" or "teen girls" are demographics whose taste is invalid (which is bound up with sexism, classism, etc), and that it's fair to dismiss something because it has the audacity to be popular as if it can't simultanteously be powerful or provocative or whatever.
The stuff I really hate is the stuff that almost aligns with my taste but fails. I love a lot of modern "indie electronic pop" ie the past fifteen years of Goldfrapp/Bjork/The Knife knock-offs. But I can't stand Chvrches or Sigrid because while on paper they're up my street, the actuality is they leave me very cold and it's more frustrating to think I've given them time because I've listened with good faith and been wholly disappointed.
I'm interested in why people dislike what they do rather than how much they dislike it.