Well that’s a stupid reply as you’re quite right, if he decides he doesn’t feel like singing anymore then he shouldn’t.
If a band doesn’t feel like making an album then they shouldn’t. It’s not up to the fans to decide what a band does or doesn’t do.
Bands don’t owe their fans anything but a section of fans think because they buy an album and a ticket to see them live that somehow gives them the right to tell a band what they should and shouldn’t do, it doesn’t.