Nah caffeine actually does help treat migraines since it’s a vasoconstrictor, and one of the effects of migraines that contributes to them being so painful is that they cause vasodilation. So basically migraine makes the blood vessels in your brain get wide and the caffeine helps get them shrunk back to normal size

I’m sure that’s the case for some people’s “migraines” that they take this sort of thing for but it does actually have a mechanism for helping with legit migraines