MEtallica is underrated if anything.
Listen to a few of the various classical renditions of their tunes like the ones by Apcalyptica perhaps to gain a better appreciation of the craftmenship that actually does go into their work, like it or not.
I like Green Day overall. Probably the best rock group these days that is still fairly popular and talented overall. Their albums are not always consistent but many great tunes.
A solid core of talent in both acts.
Guns & Roses is what they is, which is fine by me.
These are all acts/recordings that require a good sound system that can be cranked effectively to enjoy.
Many systems, even those that might be "high end" otherwise, might run out of gas quickly with either your typical MEtallica or Green Day recording. They are loud but still very good for what they are!!!!!!
Along with large scale classical works and big band, many a MEtallica and Green Day recording are perhaps among the toughest to get to sound good in a home system, but when they do, and you like this kind of music....it rocks!!!!
This kind of music and recording is much easier to tackle with portable devices and headphones for most, which is probably why that is how most people listen to this stuff.
Will anyone remember The Clash in another ten years or so?
I'll buy them as overrated, though definitely influencial. I much prefer The Cure and The Church overall.