“Relatively safe to” is a very official sounding rubric. I guess tell him that and see if you agree on the timing of when that safety threshold has been met.

Telling your kid to not drink beer is giving them the courage to say no to drinking beer. I personally don’t just bark out rules with no context. I also have discussions with my kid about why drinking beer can go awry. We all expect that they will, likely before we’d feel it’s relatively safe. So I want him to at least know what’s in store and how to not make compounding mistakes.