There are a few markets, San Diego and Detroit come to mind, that are trying "Next Generation of Classic Rock." But I think you have to be in a market that really loves rock to give it a try. I'm not sure Fairfield County is such a place.
The reason the 2019 version of Classic Rock still covers The Beatles to the 90s, is that as we grew up, most rock stations played plenty of library rock, even in the 1980s and 90s. So even if today you are in your 50s, 40s, even 30s, your rock station as you were growing up was likely playing The Stones, Zeppelin, The Who, Pink Floyd and The Beatles, both together and as individual artists, alongside contemporary acts, The Eagles, Fleetwood Mac, Billy Joel, Elton John, Heart, Tom Petty, etc. However, if you preferred Top 40, Country, Urban or similar formats, your station would rarely play something more than a few years old. Those formats were much more driven by new releases.
This is why the rock artists of the 1960s and 70s are still getting played 50-60 years after their songs were released. You were exposed to more library material than if you were listening to Top 40, Country or Urban stations. I suppose sometime in the 1990s, rock stations became specialized and stopped playing a wide variety of rock hits. You no longer got James Taylor, Jimi Hendrix, Van Halen, Sting and Human League on the same station. It split between Active Rock, Alternative Rock and Classic Rock.
Classic Rock still works surprisingly well, even in the 18-49 and sometimes in the 18-34 demos. I suppose some 60s and 70s titles are getting deleted and 90s titles are getting added. But the urgency isn't the same as on AC and Classic Hits stations to keep revising the playlist, where each year the songs that appeal to listeners hitting 54 get moved out and a new block of songs that appeal to someone reaching 25 get moved in.