Theory on the extinction of dinosaur: Leadus Guitaradon

So, what did cause the fading away of the lead guitarist?
Evolution, my dear Watson, just as it saw the fading away of the great clarinetist, trombonist from days of old.
The Lead Guitarist was common place all the way back to the early Beatles and Stones, progressing to power trios such as Cream, Hendrix and Led Zeppelin to fronting every spandex clad hair band in the 1980's. A rock and roll staple. These guys and occasionally a gal could and would steal the spotlight from even the greatest singer.

Then came the 90's and a new rock generation. Just as rock and roll toppled the crooners of the 50's, the Punk-New Wave-Grunge movement set out to topple the guitar-centric idea of rock. The New Wave movement was toward synthesized keyboards, drum machines and vocals.
It was as though it was anti-guitar and they embraced in the new technology. Blinded by science so to speak. Punk retained the old school band formula, 'Bass-drums-guitar-lead guitar' but turned it upside down and almost reveled in an inability to effectually produce melodic sounds. Grunge was the final nail in the lead guitarist's coffin.
Great rock guitarist of today are very effective rhythm aces. Make no mistake, the guitar talent is there today but it is all about chordal harmonies and rhythmic strumming. Yes, you can still buy and hear great lead guitarists but they aren't played on youth orientated "Top 40" radio.
One era is not better than the other, it's just different.
Music seems to have branched out to so many sub categories, I have no idea what they call the rock music on the radio today.
MySpace Music page has a drop down menu to list the type of music your band plays and there are no fewer than 110 genres to choose from;
Crunk, Death Metal, Grind Core, Psychobilly, Screamo, Trance, Jazz and Classic Rock to name a few.

Funny thing is, the other night I got sucked into watching part of a Public Television special. The feature was the Big Band era from the 40's; Glenn Miller, Tex Benecke, Frank Sinatra and such. The music was quaint at best and well, very dated, but I was struck by a single fact; The musicians were extremely talented, professional and not a weak or sloppy player among them. The musical arrangements were extraordinary. In those days you had to sight read music and quickly.
Today in rock, it is a rare occasion to find musicians that read music except for keyboard or horn players.
My advice to up and coming musicians; learn piano. 90% of all the music you hear in movies, TV and radio is done solely on a keyboard.
You can reproduce most any instrument sound on a Midi keyboard including percussion. I have a friend who is musical director for a fairly popular TV comedy show. He gets each show in advance, queues it up on his home studio computer and emerges a few days later with the entire show done. Just him and his keyboard. Once in a while he'll have a vocalist come in if there happens to be singing in the episode.