Turns out, quite a lot in fact.
Both COVID-19 lockdowns and the 21 drinking age were first implemented in a moment of panic during a deadly crisis--coronavirus in the first case, drunk driving in the second. While neither were sold as miracles at first, they were indeed sold as ways to mitigate, or in the lingua franca of 2020, "flatten the curve" by at least slowing down the crises and hopefully save lives in the process. Delay the peak of coronavirus cases and protect the hospitals from collapse, we were told. Delay legal access to drinking alcohol until 21 and protect young people and those they share the road with until they are a bit more mature, we were told. And of course in both cases, the more zealous of the enthusiasts sold it as a suppression strategy or even an eradication strategy rather than merely mitigation--if only they could make up their minds. The message was we could either give up some of our rights temporarily or all of our rights permanently, or at least that we had a moral duty to give up some of our rights lest we have unacceptably high death rates in both cases. And we had to act NOW, or else. No time to think it through, our brains must go into neutral for the time being. After all, the models can't be wrong, can they?
And then once these measures were firmly in place for a while, relatively speaking, their enthusiasts seamlessly moved the goalposts. Now it was no longer about preventing hospitals from collapsing (which generally didn't happen anywhere outside of Lombardy, Italy regardless of whether a country did a lockdown or not) or keeping a massive excess of blood off of the Demolition Derby-style highways, but rather about "saving lives at any cost" (as long as someone else pays it, of course) and with the 21 drinking age more recently about protecting "developing brains from damage" and other social-engineering goals. And then there is the "blood borders" phenomenon both with the virus as well as DUI. Thus the enthusiasts of both now wanted to extend these measures indefinitely, with the fear of all hell breaking loose if these restrictions are ever relaxed before a vaccine (for the virus) or better public transit and self-driving cars (for DUI)--but in the latter case they still have the pseudo-neuroscience argument to fall back on as well. By design, there is no exit strategy. And many people have been reluctant to support ending such policies since they fear blood on their hands if they do, making these policies politically a LOT harder to get out of than to get into.The supposed effectiveness of lockdowns (compared to far less extreme restrictions) in terms of slowing or stopping the spread of coronavirus has been called into serious question lately by more recent studies.
Such studies have found there is at best no correlation, and perhaps a perverse effect between the two defining features of hard lockdowns (stay-home orders and closures of all non-essential businesses) and COVID-19 cases and deaths per capita after other factors such as less-extreme policies are accounted for. The benefits are thus nothing more than a statistical mirage that does not stand up to scrutiny--much like the supposed benefits of the 21 drinking age vis-a-vis DUI deaths in the long run.
So what happened? Turns out that in the case of both, the early adopters did fare better overall, at least at first, though many non-adopters did at least as good if not better in terms of reducing death rates by using far more moderate measures. But for the belated and/or coerced adopters, both lockdowns and MLDA 21 turned out to be worse than useless, essentially pouring gasoline on the fire after the train has already left the station, and with plenty of collateral damage. And while the book has not yet been completely written on the coronavirus pandemic saga, for the 21 drinking age we see even for the early adopters, the benefits were short-lived, and really ended up just delaying deaths by a few years, both from one cohort to the one one behind it, as well shifting deaths from the 18-20 group to the 21-24 group, possibly even resulting in a net increase in deaths in the long run. Much like how for lockdowns, at best they delay some deaths by a few weeks compared to more moderate measures even when done early, at great cost to the economy and society.
Meanwhile, the collateral damage of lockdowns (economic depression, unemployment, inequality, poverty, alcohol and other drug abuse, domestic violence, child abuse, loneliness, poor mental health, delayed medical treatment, etc.), which also kills people too by the way, continues to mount with each passing week of lockdown, making an utter mockery of practically all progressive and even basic humanitarian priorities. For the 21 drinking age, this collateral damage has resulted in forcing alcohol use underground and making it far more dangerous than it has to be, and people being reluctant to call 911 in the event of alcohol overdoses and injuries, and that maims and kills people too. And for both, that's to say nothing of the damage to civil rights and liberties, culture, and community cohesion, that progressives would generally support.
As for protecting the most vulnerable members of society, we have seen this movie enough times to know how it ends, and it doesn't end well. Both measures are far too crude to do actually protect them, and sadly but unsurprisingly, both have failed miserably in that regard. Which is usually the case with such "blunt" policy instruments in general. We know who the highest-risk groups are. Thus, a more "focused protection" strategy in both instances is thus called for, provided that it still respects human rights.
In other words, even when done early and enthusiastically, there is no short or long term benefit that cannot be had by more moderate measures done early and enthusiastically. And in the long run, especially when done after the proverbial horse has bolted, the "cure" quickly becomes far worse than the disease. And when we look at the control group--that is, those jurisdictions who did not take such measures at all--the case for both collapses.
Let America be America Again. And end both bad policies yesterday, as both have by now long outlived their usefulness. What are we waiting for?