I think a lot of public high schools in the USA teach complex numbers and linear algebra. Maybe not at the level of finesse or rigor of a high-quality college course, but what does that matter?

US education frequently doesn’t even touch computer science. Some schools have after-school programs or AP CompSci, but it’s somewhat rare in my experience. Why not start teaching that, instead of banking on the hitherto dubious value of existing quantum computers?

So do many classical computer algorithms.