I think everyone probably has only so many spoons, it's just that if you are young and healthy you have so many you don't get depleted often, and so you don't have to think about it much.

I've actually heard the opposite from some people - that they don't like it when TAB people use the spoon terminology, because there's a big difference between, say, someone with ME/CFS being out of spoons, and a TAB person being tired at the end of a very long day. I've heard it argued that this is in fact a qualitative difference, in the type of tiredness, rather than just a quantitative difference of how tired you are.

(I don't have any of the relevant illnesses, so I can't speak for them, but I was interested to hear the different point of view.)