What's interesting to me is the nostalgia boom for artists who either kept going or reunited, and the crowds now are far larger than what they were back in the day. The Pixies filling a 5000 person venue? Morrissey with a Vegas residency? I don't think either charted on the Billboard Top 40.
I knew a musician who was a star overseas, and during the 90s could regularly sell out large venues. He packed it in after about 10 years. To him it really was a grind, there were diminishing returns as his core audience grew up and moved on, and he was operating in a relatively small market. He ended up doing real estate and business development in a second country where the economy was booming, and had a moderately successful career doing that. He doesn't seem to be interested in performing anymore.