Depending on the style of the climb, ultimately I’d prefer to err on the conservative side and have more food than less.
For winter trips, I’ve used the 1kg/person/day (dehydrated weight) formula and everyone ate nearly everything (group of 16).
Although if you’re going for an alpine style climb and are willing to risk insufficient calories and the results of that, I imagine it’ll be pretty individual specific (aka bring more food, see how much is left, do another trip and bring less food, see how much is left, etc).
Although just because one is doing an alpine style climbing doesn’t mean one can’t be successful and have a full belly –
I finished with four days of extra food, 250ml of olive oil, but only one leaf of toilet paper. It was a very close call on the toilet paper and I was happy to make it down before I ran out!