As I said: musical talent is a prerequisite for me to consider a band "good." It is NOT all that is important, but it IS important.
Premise: For, me a band must be instrumentally skilled to be good.
Second Premise: The Ramones were not instrumentally skilled.
Conclusion: I do not consider the Ramones a good band.
Premise: A band does not need to be unbelievably good at their instruments for me to consider them good, just better than decent.
Second Premise: The Black Keys are not unbelievable musicians, but they are above average and write good, bluesy music.
Conclusion: Despite their not being the best musicians, I like the Black Keys.
And, to be honest, I don't listen very much to Fugazi or Husker Du and I don't really have any interest in giving them a long look at the moment.
All the musical skill in the world doesn't make up for being shitty musicians. Music, in the end, is about
sounding good. Example: none of the Rolling Stones can play their instruments for shit, with the possible exception of Keith Richards and Mick Taylor; but they are (were) a great band. Despite their near complete lack of technical ability, they still wrote good music and sounded good together. If all it took to make a good band/good music were talented musicians, then 90% of prog rock/metal bands wouldn't be the absolute shitpiles that they actually are. See, for example, Dream Theater; fantastically talented musicians, but for the most part a terrible, terrible band. Van Halen, Eddie is one of the most technically amazing guitarists ever, but his music sucks (this can be applied to most guitar wankers, actually).
Basically, the first priority for good music cannot simply be pure chops. There are way too many technically proficient people who just make shitty shitty music for this to be reasonable.
Anyway, back on topic, U2, The Beatles, Radiohead, Bruce Springsteen, Explosions in the Sky, Pink Floyd, Kanye West, Muse, and yes, the Sex Pistols, are overrated.