Dunno man. When enough people overweight, 1-2 alcoholic drink become healthy (alcohol is a blood thinner): this happened, but as we know now it's not true.
https://theonion.com/report-aspirin-taken-daily-with-bottle-...
Source?
Doctors mostly tell you not to drink because it’ll fuck with the anesthesia math and bad anesthesia doses can kill you just as dead as a surgical mistake and probably moreso. But it’ll also make you bleed more.
If you need courage to show up to surgery they’ll give you a prescription for a single dose of a benzo. Which is better than liquid courage anyway.