Where did "commitment" even come from? Not that the manifesto is a sacred document but it's not mentioned there. It's something that got bolted on later as a way of extracting more labor from developers by exploiting optimistic estimates and bravado in sizing exercises (something else that got bolted on by consultants as far as I can tell).
Scrum, in some of it's fundamental practices, is antithetical to agile but this tension is actually great because it justifies a parasitic priestly order in the form of consultants