So, easy recap. I asked how you measure how good a guitarist is. You responded that his ability to replicate leads varies in quality. I responded and asked what guitarist defies that. You said Paul Gilbert. I found a video of Paul Gilbert clearly not at his best in 5 seconds.Kirk's stuff was never that technical, and a lot of times, his stuff is not that discernable as to what he is playing. This wasn't really much of a proven point, but okay.
My 1st point was that this stuff is horribly subjective. My 2nd point was that everybody eventually declines. I'm not sure if you agree or disagree with either of those, but I'm still not seeing how Kirk is bad.
To me, he's a guitarist who once played some adequate leads for some iconic songs from forever ago. He was never the same calibur as Paul Gilbert, Marty Friedman, or Yngwie. But he's also not a Kerry King or an Ace Frehley. Also, Yngwie is no longer even able to play his own stuff half as good as half his fans anymore, so maybe judging Kirk 2023 vs Kirk 1986 isn't really a fair gauge.
Like has been said a dozen times in this thread, Kirk fits the glove very well of "I've been playing for a few months and want something challenging to learn that sounds iconic but doesn't require superhuman ability." So stuff like Master of Puppets or Seek and Destroy can make a stepping stone for budding players. Not everyone is able to pick up a guitar and learn Cliffs of Dover for their first solo piece. Likewise, no one goes from Come as You Are straight to Under a Glass Moon.
Is Kirk over-rated? Yeah, they all are... all the icons. The guys really doing crazy stuff are the ones the icons listen to and that the general population doesn't understand. But there are a lot worse than Kirk.