I can see your point; OTOH I cannot count the number of times in 5e (or other editions either) play where I sat there thinking "is it time to expend X in order to end this encounter quickly and avoid taking some more damage?" X could be a spell, superiority dice, etc. In this sense, I think hit points CAN be seen as very akin to a meta-currency, they don't represent any specific thing in the fiction, and you often shape your play around their expenditure or saving. I mean, I agree, its not quite like superiority dice, or hit dice, or spell slots, where you literally decide whether or not to expend them at first hand, but its not far off!