My understanding was just the opposite. One of the problems with trying to vaccinate against Winnie-the-Flu is that supposedly corona viruses mutate about as fast as the flu.

There's also the Mink variant that Denmark(?) basically purged their domestic mink population to keep from spreading, not to mention however many that don't even qualify as a variant, because they're not quite different enough identify as a new strain...

Honestly, at this point, we'd probably be better off accepting this thing is endemic and just going about our lives. Hell, half the viruses that cause the 'common cold' are corona viruses anyway...