We had a big (for Seattle) snow dump overnight, which means I won't be going anywhere for a few days. Fortunately the forecasts were accurate this time and I was able to stock up with groceries. It looks pretty out there.
Yes, a host that dies before it can spread the virus is less beneficial, effectively creating a dead end. Over time the probabilities will favor evolution that maximizes transmission, creating a trade-off between replication rate and lethality.
I'm not expecting it to mutate to a less harmful form any time soon because the population groups doing most of the spreading are not being significantly impacted health-wise. There's little evolutionary pressure to get the virus to become less lethal.
The club said the biggest impact he had was his leadership; he (and the coaches) instilled a winning attitude in a club that had been perennial also-rans.
According to J&J:
Phase 2 uses 1,000 subjects for safety testing.
Phase 3 uses up to 60,000 subjects to judge efficacy.
https://www.jnj.com/innovation/the-5-stages-of-covid-19-vaccine-development-what-you-need-to-know-about-how-a-clinical-trial-works
It reminded some people hereabouts of the 2013 Superbowl in which the team with a dominant defense and a moderately capable offense crushed a high-powered offensive team with an average defense. We always respected Coach Arians when he coached Arizona; those games were tough. Not to mention the injuries...
Not surprisingly, the Congress critters who have contracted COVID-19 are predominantly Republican. I suppose you can say they're taking one for the team, but the logic is daft.