I have a lot of alcoholics and other addicts on both sides of my family. I was brought up knowing I most likely had "the gene" and knew a lot of AA speak from being tiny (I remember being at an Al-Anon convention as a toddler!).
The abstinent members of my family vilified alcohol, told me to never touch a drop, the co-dependent members of my family said they hoped I wouldn't drink and it was rare that we had any alcohol at home (as we didn't want to set off the alcoholics and I needed one parent to not drink).
Anyway, there was never any encouragement from my family to try alcohol, quite the opposite. I got to try Baileys and Bucks Fizz etc but it was never sold as grown up or special, and I actually think that was key for me.
People have generally weird attachments to alcohol, it's a little bit fun and naughty, or it's absolutely vital that mummy drinks gin/wine to cope with stress, or it's an expectation that you HAVE to drink or you're weird (or a secret alkie), or it's bad and you should feel ashamed, or it might change your personality, or it's ever so grown up and sophisticated etc... It's just bloody juice at the end of the day...
I swore at 12, I'd never touch a drop and I didn't at teenage parties etc. At 22, I was a bit curious (and wanted to test the gene theory)...I binge drank on a girls' weekend and puked up what I thought was blood but was actually red bull. I discovered that the gene had no impact on me in terms of alcohol. After that waste of time and tge next day of my life I'd have the occasional one (two at most) drinks...usually vodka and coke or Archers and Lemon but honestly it was only because of social pressure. I didn't see what all the fuss was about.
Now I honestly don't give a shit about booze. I think it's a waste of time and money for me personally.
I hate the pressure that there is to drink to make other people feel better about their own drinking - I think that's a massive problem in our society. I hate people who will not take no for an answer, "go on, just have ONE, one won't hurt you!!!". No, it really won't but I just really don't fancy one...I genuinely prefer a nice soft drink. And you don't want me to have one for me, you want me to have one for you...what's that about?
I get around it by having something that looks alcoholic but isn't...coke in a whiskey glass, or ginger ale etc. I've got a merry enough sober personality that the pissed people don't realise I'm not drinking and leave me alone to actually enjoy my night without the boring pestering. I don't judge other people for enjoying their drink, but I do judge them trying to force it on me. I don't go around advertising that I don't drink by the way, and was once given the advice to carry half a glass of wine around as a prop at social events and not actually drink it to get people off my back.
So my upbringing around alcohol was strict, and I've grown up very much that I can take it or leave it but get more enjoyment out of life when I leave it.
I'd say rather than worrying about when to give alcohol to a kid, focus on teaching them about behaviour, pressure, dependency etc. Don't make them feel like they have to drink to be normal, it's really their choice. And if they do drink eventually, maybe teach them to not pressure non-drinkers to join in.