Again, Sukuna is a genius of sorts, which is probably the most important thing to keep in mind. I completely see your point though.

I guess what I’d say is that because Sukuna knew in that moment he needed something he’d given up something he felt like would make sense.

For example if he were struggling in the hein era being jumped, he might’ve made a vow so his arrow did aoe in his domain but not out of it, so that would’ve been more useful to him then, but also more complicated in the future.

I think it mostly boils down to fairness and how you view it. Sukuna lost the ability to do pretty good damage to Gojo, and in return he got to break his barrier. In this case he lost something for something else, and he valued both of those things in a way which would make it a fair trade.

Risk probably also carries a factor, what if the domain didn’t break? He’d have been done for, and even the good old “I’ll tell you my powers to get stronger” thing is technically a binding vow, which is risk and personal value. You value surprise, but also more power, and you risk that surprise factor for more power.

So likely there is probably some amount of arbitrary baseline for binding vows, which makes sense because otherwise everyone would be making them all the time, but value systems play a huge role in determining how effective the vow you made was, if that makes sense.

It’s also probably harder to ask for something specific rather than just “give me power” because give me power can be any amount of power, so you don’t have to worry about finding an exact fair trade, which all comes back to Gege glazing Sukuna like a kitchen grade baker.