Late 60s/into the 70s we had the pioneering guitar gods....Hendrix, Page, Blackmore, EVH.....and that culminated in the 80s with virtuoso guitar going to it's highest points. EVERYONE had a shredder on lead...hell, in Mpls you couldn't even get in the door to tryout unless you were a king shredder of some type. And, you HAD to have great stage presence. Big hair, big sound, great players. Now, the songs themselves weren't always great but the guitar playing usually was.
The 90s, was the antithesis of the 80s. Great songs by great bands like AIC, Soundgarden, Tool, STP etc but no one gave two shits about lead playing anymore(not including metal though). Nor did they really care about stage presence, or at least it wasn't the biggest emphasis.
Closer to the 2000s we had nu metal, now there are NO lead breaks in many tunes I'd cover in bands I was in. Different, scooped and fizzy as fuck bad rectifier tones (which is too bad since Rectos don't sound bad at all) but some stage presence came back; dudes are slinging their guitars WAAY down and pointing the neck WAAAY up, so I guess I understand the lack of leads since you can't hardly play rhythm that way. Lol.
Into the 2000s everything started to die down and only Alter Bridge kept me interested in any new releases...still not a lot of lead playing in rock but still had 7Dust and a few other 1 hit wonders to download from time to time.
Live playing has really died down in my area too, which is sad....back in the day, the 'cowpie' circuit as we called it, any little shit town within 50 miles of where I live, wanted bands every weekend...now there's maybe 6 places total to play if you're a local act.