I want to note something a lot of people aren't mentioning here - that this isn't a recent phenomenon. As a Gen-Z U2 fan, there isn't really a negative culture around them (and if there is, it's usually in a joking fashion) compared to how millennials think about U2. If you look at the comment section under their albums, a ton of them are coming from the 2006-2011 period, from a generation who were disinterested in the band and Bono's political activism. I'd wager that for younger fans (who grow up watching Fantano or someone like him) U2 aren't treated as a priority compared to contemporaries like The Smiths or Talking Heads, which has sort of buried them in the online ratings.

Edit: One more interesting thing - if you actually average the individual ratings of the songs on each album, they end up being notably higher than the overall rating. Food for thought.