It will soon evolve into another common cold. The sweet-spot between producing more viral particles and not making its host too ill to go out an interact with other potential hosts is towards the mild-symptom side.
This has happen three times in the last 20 years that we know if. So it has probably been going on forever. It's not like nature hasn't had an opportunity to develop a super-deadly coronavirus. It hasn't yet. And it's probably not going to.