Further mutations should be less severe. A virus job is to infect, replicate, but ultimately survive, so if it kills the host, it dies with it, which defeats its own purpose. One of the ways it survives over time is to mutate into a less severe form. Reading the epidemiology of the Spanish flu would alleviate a lot of unfounded fears about future mutations, and there’s a reasonable probability that the quicker we move through them, the quicker we will just consider Covid a seasonal virus and not a major threat to life. The connotations of the word “mutation” are pretty negative, it’s not the nicest word, but they are a way out.