The thing is, with music or any art form or, indeed, loads of other stuff, there are broadly two ways to measure them - popularity / utility and 'quality'. Sometimes the first is a function of the second, but not very often. It's quite difficult to keep these two separate and attempt to be objective about it. It's a good mental exercise and stops you turnig into either a pub bore or an intolerant tw*t but it also makes for potentially dry conversations or exchanges of views.
So in the spirit of objectivity...
Morrisey is not 'rubbish' in either of the senses - he has written good songs and can hold a tune and his music has been very popular.
Wetherspoon's food: no idea, only ever been in one of thier pubs once and the beer was cheap but the floor was sticky. Not for me, Clive, but people want somewhere to meet and have a drink and some food and we can't always be making those kinds of decisions based on our agreement or otherwise with famous owners. I am rarely in England and when I am there are lots of excellent pubs I can go to and get beer I like in a pleasant atmosphere, which I accept I have to pay more for.
Ian Brown can't sing but I still enjoy his vocal delivery, partly because I can sing along to it and not sound awful! Liam G can't sing and I don't like thier music but I understand they are popular. Coldplay I just don't get but I think they are largely music for people who don't like music and they perform a valuable function of making a lot of people feel happy.
If you want to find genuine total rubbish you just need to put a random word into Spotify song search and have a listen. Plenty of qualitatively awful music with almost no listens. It gives people somethign to do and an outlet to make them feel better and it hurts noone sitting there so it is harmless, but it is absolute twaddle.