He might play every day in private, but I think Felder means he lost interest in being a professional musician. Even when he was a recognizable name in the 70s, he only put out a joint effort LP and didn't tour behind it. Later efforts were sporadic. Why? One can only speculate.
Bernie did release an album in 2004 called Mirror, his first completely solo effort, but he didn't tour for it outside of a few special promotional appearances. His jaunt with the Eagles was a thrilling surprise; I think it took something of that epic scale to get him out in the public eye again. Thank goodness he said yes!