Exactly this. The whole “viruses evolve to be less deadly/severe” trope is just wishful thinking masquerading as science.
Evolution isn’t some sort of get-of-pandemic-free card, no matter how much we all wish it was.
There’s lots of counter examples of viruses that are still as deadly as ever, but I’d go beyond that; I’ve never seen anyone give a concrete example of a virus that actually did evolve to be less deadly.
The closest anyone has come to that is the 1918 flu pandemic, but there’s no evidence that it’s less deadly now due to evolution. It’s more like that it is simply less deadly because there isn’t as much widespread malnutrition as there was in 1918.