If you'll let me put my tin foil hat on, I would say its possible that personal finance isn't taught deliberately - banks want people to be worse at money and debt management so they can make more money off them.
Public education seems to me to be one of the few sectors that big banks exert little to no influence on. The main problem is cyclical, many teachers and administrators never got this training, and so aren't well equipped to teach and advocate for it. Much of education curriculum setting (in terms of what classes to teach) is driven by union demand, so a lack of accounting/finance teachers leads to less advocacy, while a surplus of visual arts and music teachers leads to substantial demand for those classes.
Yet, when budgets increase, these are the first to return, and the useful classes are never offered. I'm not arguing that art and music teachers end up unemployed first, but their existence is still what drives the lobbying for these programs. Government education policy (at the curriculum, not budget level), is substantially influenced by teachers unions.
I'm sorry but I don't believe this argument at all. Unless grade schools are no longer covering reading, basic mathematics, and even basic chemistry and biology I don't think there isn't one skill I learned in school I don't use everyday, except Spanish, I was horrible at that.
Now my university level intro to Architecture, while I appreciate it, is something that I only put to use at cocktail parties.