I have had the great privilege of growing up with rock since the 60's, and playing in rock bands from 1965 onward to the present. While always an avocation not a vocation, it's nevertheless been the single constant in my life as relationships and jobs and homes have come and gone.
And sadly, I have to agree that the section of musical space/time occupied by rock has pretty much all been explored, charted, composed, played, and in many cases, played to death. Hard to imagine what a truly new rock innovation would be, and I don't see anybody coming up with one.
So our job is to keep the existing body of music alive by continuing to perform it as long as there's anybody interested in listening to it. Eventually those folks will decrease in number, and another musical era will close.
Fortunately for me, I'll probably be gone by then. I intend to keep playing as long as my fingers work and my brain can control them. But all things come to an end eventually.
And still there is a lot of music that was made in the 60s and 70s that is still to be discovered, and thanks to YouTube and other Internet sites, it’s all out there now.
Well at least hopefully being in a band will still be a good way to get the chicks. ;)