I'd like to agree but the evidence suggests differently, e.g. [1] Arguably, there was an increased awareness in the US of drunk driving as a problem during that period but the effect still seems to be real even correcting for that.
Of course, if we assume a completely different culture around alcohol, the results might well be different.
Ah, I should maybe have been more clear. My point was that it would have better effects to change the culture around drinking, rather than increasing the age limit of when you can drink.
I’m not suggesting that it’s an easy thing to do though.
If this were a universal thing, I could see it helping, but unfortunately I'd be surprised if only people who opt in having this feature makes a significant dent in the issue.
Of course, if we assume a completely different culture around alcohol, the results might well be different.
[1] https://www.ncbi.nlm.nih.gov/pubmed/20497803