I don’t really know booze very well, so my initial thought is whiskey, which, according to this bottle, is 90 proof. I’m inclined to agree with you.
The CDC actually recommends cleaning wounds with just soap and water, as alcohol can damage the cells that help close wounds. I would think this would reduce the player’s healing rate because of this. But, specifically for disinfectant, yeah, I feel alcohol should be viable.
Especially because we count hydrogen peroxide as disinfectant, when in reality, it’s pretty trash at disinfecting.
My guess would be that hard liquors spawn pretty much everywhere, so making alcohol a disinfectant would trivialize bite wounds (more than the availability of first aid kits/peroxide already have). That’s just my guess, though.