Haven't had the flu in 10 years or so. Back when I was working I used to fly all the time, all over the US and Canada and I think I got a cold or flu at least once a year. Never got flu shots then either. Now being retired I don't come in contact with near as many people as I did when I worked and I get a flu shot very year. Seems to work.
Watching CNBC today, Gilead has now priced Remdesivir - $3,000 for treatment (via IV). It is administered to people who are hospitalized for COVID. Supposedly cuts recovery time by 4 days, so you'd save on 4 days of hospitalization if it works as advertised. Gilead is under some heat because they charge $3K here in the US, but around $2K to other nations.