For people, the difference between 2% and 0.2% mortality is huge, but for the virus (and the evolutionary pressures on it), the difference between 98% and 99.8% chance of continuing to spread is insignificant; any minor changes in the rate of spread far outweigh that. The evolutionary pressure towards survival of the host matter only for diseases with very high lethality.
Being more severe and deadly is not necessarily a propagation disadvantage.
Because if you sick you stay at home and don't go out. If you are very sick, you need to go to the doctor, or the hospital. This can create more spread.
> Yup, tradeoffs forced to select towards survival.
Viruses don't have a plan, or intent. It's not impossible for a virus to screw itself over and kill off all its hosts, or one species of hosts.
wow, suddenly I feel like the film "Venom" was trying to teach me this, it's no good for the virus if it keeps killing its hosts, really its mutating itself while searching for a host that can coexist with it (as I understand it, much of our DNA is incorporated from viruses, but I don't understand it very well :)
It already coexisted with a host: bats. If we're going to anthropromorphize the virus, maybe it's searching for a way to kill off one of the biggest predators of its preferred host.