I'm not sure, but you might be greatly underestimating the rate of evolution for these virii. Generally it is ~10^9 faster than eukaryote evolution (https://viralzone.expasy.org/4136) and there are many (10^?) generations that occur in every host. Early selective pressure for fast replication makes it deadly, but late-stage selective pressure is to be transmissible through mild symptoms. The end game is that it becomes part of our DNA.
I might also mention that the virus doesn't really care about us. Mostly it's interested in infecting our bacteria. That's kind of a joke, but in reality, it says everything about how to control it.
We have a pretty good idea how fast corona virus evolve. Yes there will be selection pressure for it to become less deadly, but this can take a long time. My proposal is how we can speed up this process.
