It's one of these areas where people (including medical professionals) hold strong beliefs, but then it turns out that there are other highly-developed countries where this is not routinely practiced, and the outcomes aren't necessarily different.
Routine wisdom teeth removal is not a thing in most of Europe. Another random example are colonoscopies and routine flu vaccines (except for the elderly).
I've generally assumed the simplest explanation is that many of these weakly-supported procedures are regular, consistent income streams for the people who perform them in the US: my four wisdom teeth (that were causing me serious issues at age 19) cost $2k to remove nearly 20 years ago, and I know colonoscopies are billed to insurance in the thousands. There's not much incentive to move to cheaper tests or wait-and-see, when you can just do it to everyone who reaches a certain age by default.
Presumably flu shots are good business for the manufacturers, though I'm not sure about the science. After having the flu as a healthy late-twenty-something a while ago, which was...intensely horrible, I've chosen to get it ever since.
It's not always true though. My dentist in Europe pushed me to get my wisdom teeth removed early "because you're going to need to get them removed eventually anyway" at a government clinic with no profit incentive.
Not sure which country you're talking about, but in Germany, the public health insurances cheerfully pay for annual flu and COVID boosters for everyone.
Flu may not be too dangerous in people who aren't elderly but it still sucks. Can a non-elderly, not in any other high risk group, person get seasonal flu vaccination in Europe if they ask for it, and is it covered by European health care systems?
They're not only covered by the gesetzliche Krankenkassen (German public health insurance providers, mandatory if you don't meet the criteria for private insurance), mine gives me a little bonus if I prove I've gotten various vaccines, including annual COVID booster and flu.
This guy infamously has a problem with each and every HN user and chooses to display an NSFW image saying such if your request's referrer header has news.ycombinator.com. Don't click.