A few reasons.

First, the alcohol industry has been a lot more sensitive to being perceived as selling to kids than the tobacco industry was. Because of it, there was never the push to ban advertising and conduct a mass media effort to control teen drinking as there was teen smoking.

Second, people still remember prohibition in the USA and how it was a failure. So, you’ve got a lot of people worried about a slippery slope in comparison to tobacco.

Third, the alcohol industry is far better at lobbying around specific items that would actually prevent consumption. For instance, alcoholic beverages don’t need to show nutritional information. It will bend in a way that keeps access open.