I've felt exactly the same way for a number of years. But in the early 2000's, I played with an original band that once they found out I could play it, kept wanting to use it in shows. This is indie Lincoln Park in Chicago, and an all original band/show/venue. Shred was not something people did, so I was always kind of embarrassed to play it. For those of us who grew up with it, it was the benchmark- 25-30 years ago. But even ten years ago, it seemed just old. However, whenever I played Eruption, it always got this overwhelming response. Especially at the descending tapping part, everytime. I can play it, but I always felt that the crowds response had more to do with the song, and less to do with me.
The thing is, even though it is old to us, there is still some kid in his room somewhere wanting to learn; waiting to be blown away, like I was; like we all were.
IMO, this is why the KISS machine still works. When I was first exposed to them (around '78/10 years old) They were larger than life. I am sure this still has the same affect now. Interestingly, the 10 year olds today may or may not understand the importance of Ace or Peter, but they will still stand there with GIANT EYES when the stage explodes in front of them.
I think for the fact that you performed it in front of a bunch of people who had such a cool response to it is all supporting evidence to this.
Hell, my 22 year old daughter, who loves all music, just came to me the other day and told me how much she really loves Zeppelin........pretty cool.
Interesting to see how music stretches through time.