There are really two axes that everyone seems to conflate into one. There is funding, as in whether or not there is sufficient funding to achieve certain outcomes. Then there is competence, as in managing the resources to achieve certain outcomes. Both are necessary but neither sufficient by themselves, only together.

The U.S. seems to be stuck in a loop wherein the available funds are argued about endlessly, and everybody acts as if that's the only dimension about which to speak and win. Not nearly enough is done to boost competence in the government sector. I think this is plenty true even if we set aside the current U.S. administration in which a number of federal entities are headed by naked toadies (to be fair, it's certainly not true of all federal organizations even now).

I tend to agree with you that the U.S. is probably not taxing enough for consistently high-quality outcomes in areas where the government is responsible. Yet I'm sympathetic to those that point to places where tax rates are high and so is wastefulness. But when the only lever it seems that can be pulled is on the revenue/spending, it's no wonder the correlation between that lever position and good outcomes is low - it ignores the competence with which any of those funds are managed.

I think it's entirely possible to have competent government if that is made a priority and addressed with some flexibility.