So, you're right that higher NATO spending is bad for the US. That's why historically they haven't pushed for it. But now the US is im the grip of nepo baby morons that have no understanding of anything. They think army guys & bombs are le hecking epic & that's the extent of the reasoning. See also: like every hereditary monarch ever.

European democracies obviously do understand the long term implications which is why they're taking the opportunity to arm up.