In the event of a court trial? That likely would come into play. The argument that the defendant was also too inebriated to make an informed decision. I don't know what the legal equivalent of "mulligan?" is but.. yeah
But... how do you prove that you were drunk enough? Were their witnesses? Why the fuck would there be witnesses in your bedroom while you are hooking up? It very much becomes "he said, she said" with the path being character assassination. And if that comes across as "massively fucked up and unfair" then... I strongly suggest researching how the average rape trial goes.
As for "how drunk is drunk enough?" That is very much a question. And is why it is good to have "the talk" with a potential partner. If they are at all slurring their voice or seem "drunk" then you take a raincheck. And if this is some rando who drank half a bottle of whiskey but still seems good to drive? Maybe be a bit more selective on who you stick it in?
And yeah, I’ve woken up with women I wouldn’t have been with had I been sober. Was I raped? Nah, I was just being a drunken idiot.
Honestly? You know you. But understand that we have decades (probably closer to a century or two?) of indoctrination to make people blame themselves for "being taken advantage of". How many sitcoms have "the walk of shame" where one of the main characters drank too much, "slept with" someone they didn't want to, and is now shamed as a slut or a fool because they woke up the morning after with them in their bed? And how often is the abhorrent admirer portrayed Urkel-style with "I'm gonna wear you down"? And that applies to men, women, and everyone in between.
Because yes, it is very much a question. And... because of the legal system and society, it is almost never in a victim's interests to actually press charges. But people need to learn: "I drank too much at a party and someone I didn't want to have sex with convinced me to have sex" is not "I was stupid". It is "I was coerced into sex". And whether an individual considers that rape is very much a personal thing. Legally? it is. But I am not going to blame anyone for wanting to avoid that word for the purposes of their own sanity.