Are you sure? Have you done the research? They had this discussion in Iceland recently and I think they found this point inconclusive. I think health officials still favored moving out of permanent DST into permanent standard because they know the health benefits of good sleeping, and they know that many children are sleep deprived.
Iceland is significantly farther north than the northernmost point in the continental US, so what is best on-balance for Iceland on a matter that has to do with the relation between social schedules and the sun is not necessarily a guide to what is appropriate in the US, even if we assume the correctness of the judgement in Iceland.
Which is not to say that you are wrong to question the evidence, only that “Iceland found…” is itself of not much value in a discussion of US policy on the issue.
This was linked by another commenter, and I think it's pretty strong evidence: https://www.sciencedirect.com/science/article/abs/pii/S01676...
And considering that they'd be getting hundreds of hours more daylight after their working day for the entirety of their adult lives it seems like a more than fair trade.
Teenagers are far more resilient than young kids when it comes to this kind of thing. Extending the portion of the year that parents can let younger kids recreate outdoors in daylight has far more societal benefit than whether a teenager is 10% more irritable. The teenager problem could also be solved by letting them go to school on their own and decoupling their school timing from adults work schedules.