Why not just have a two drink limit? Seems that would be fair to those who drink responsibly but mostly prevent overindulgence. If someone boards the plane showing signs of intoxication, preferably they leave the plane....but at worst they don't get served.
Many passengers still bring their own on board so a 2 drink limit would not work in that case. Yes, it is NOT supposed to happen but it does. In Nov 2019 I witnessed a drunk passenger continually stealing alcohol from the beverage cart and pouring his own. I pointed it out to a flight attendant and they ignored it. He was blithering drunk and yet it continued. He was a mess by the time we landed in ATL.
