Bring back Prohibition.
Older than 21. Raise it even higher!
Leave it at 21 (in the USA).
Other (please explain).
“Most people do not listen with the intent to understand; they listen with the intent to reply.”
― Stephen R. Covey
Btw, before that and a bit after, you could drink in any bar, purchase any alcohol with an active duty military ID no matter how young you are.