I think the logical thing is to have those who most benefit from the infrastructure our taxes pay for

The poor benefit from roads, schools, firefighters, Medical/Medicaid, and utilities as much as anyone. But I think you had the super wealthy in mind. “Those who benefit from infrastructure” is an odd way to pinpoint the super wealthy.

Those who “most benefit” would be those who have been able to leverage the infrastructure and security provided to profit wildly. Not those who are just scraping by.

I think we do agree on all but degree like you said. And maybe mean/median income is too high. I was just trying to come up with a somewhat natural but objective breaking point. I think a more reasonable but also more subjective one might be the “living wage” which will certainly be much lower than mean/median but also much higher than $13k.

P.S. Tangentially related, I found this living wage calculator which put my current LCOL residence at ~$42k and my previous HCOL residence at ~$57k. Turned out to be much closer to Mean/median than I expected.