They're an entirely different type of virus. There are a lot of coronaviruses other than COVID-19. For instance, SARS and MERS. Those didn't cause major epidemics because they were too deadly and fast-acting to spread far. Influenza A and B is almost a domesticated virus at this point because it doesn't (often) kill the host and its spread can at least be mitigated reliably.
More like with the constant variants, one is eventually going to become the dominant type of strain that spreads really well and doesn't kill all too much, so people won't care as much about it. The killer strains scare at least sensible people enough to do something about it. Once they're down to strains that are flu level, people stop caring and it's just another part of the landscape.