In Korean, the grammatical structure A/V+ 해 봤자 is a powerful means to convey the idea that an action or situation is futile.
Often paired with 소용없다 (it's of no use) or 안 되다 (it can't be done), this form emphasizes the inevitable or unchangeable nature of a given circumstance.
Using A/V+ 해 봤자 in daily conversations is a concise way to express the inevitability or pointlessness of a situation or action.
It's a structure that can efficiently capture the nuances of the speaker's feelings toward a particular situation.