Someone does not need to be visibly drunk to be impaired and have brain damage from consuming alcohol… especially a teenage or young adult whose brain is still developing until mid-20’s.
If you cannot understand that, then I feel sorry for those who look up to you as you serve them alcohol.
My kids are in the 20-25 age range. We give them (if they want) some of the wine from kiddush on Shabbos and Yom Tov.
My kids are now at an age where I do not tell them what to do or not do. However, they have learned the value of sobriety from myself and my wife, neither of whom has *ever* been drunk. My kids do not (and did not) go around drinking on Purim and, to the best of my knowledge, none of them has ever been drunk either.
If, despite that, you think that a quarter cup or less of low alcohol wine is going to damage them, then I invite you to call the cops on me for abuse.
The Wolf