"how little risk it poses to people our age."
You know the age of everybody on HN? And that also ignores the risk of long covid, and the risk of serious harm.
And even for young people, the risk is nothing to sneeze at (pardon the pun). See e.g. Penn State's Athletics department numbers of a 15% infection rate on their football team: https://www.centredaily.com/sports/college/penn-state-univer...
Worse, many of those infected in that particular group have rather alarming levels of myocarditis. Their age didn't spare them.
That doesn't mean we should be all "we're doomed", but glibly dismissing the risk isn't helpful either.
And while you personally might be at a lesser risk, everybody you interact with now inherits your risk. (Pre- and asymptomatic spread is a thing, isolation is not a panacea). So at the very least, include your contacts in your risk calculation. You want to see your parents and not risk killing them? Your bar of risk you can take is lower.
You spend your time exclusively with the same 5 people, in a lower age bracket, and none of them venture outside that bubble? Sure, your risk is much lower. But few of us are in a non-family bubble of 5 people who don't see anybody else.