"Status" laws have always been difficult to uphold or enforce. In the 1950s in America there were laws popping up that made it a crime to be an addict. What exactly is or how exactly to define an addict was unclear, and eventually these laws were struck down as unconstitutional, because you can't punish someone for drug addiction because it is a status versus an act, and being an addict doesn't mean that the person has engaged in any illegal conduct. Robinson v. California, 370 U.S. 660 (1962).
In immigration law, it remains on the books that a person who has at any time been a drug addict or abuser may not become a citizen or immigrate to this country, but that law hasn't been enforced in a long time too, and in fact, when an immigrant gets in trouble and is at risk of being removed (deported) proof of rehabilitation is accepted as a defense against removal, even though technically that proof would be evidence of a drug problem to begin with.
In California, the State Bar moral character question as it relates to drug use is whether or not the person's use of drugs or alcohol would presently affect his practice of law.
President Biden's son Hunter is charged in connection with allegedly lying on the application to obtain a firearm by answering No to whether he was addicted to drugs. But this sort of thing gets back again to "status" of whether he was really addicted to drugs in the first place, and then the constitutionality of the law to begin with. Someone could be addicted to drugs or alcohol and still be functioning and another person could be not addicted and drink or use enough to be a danger to himself or others. And how to define whether someone is addicted or not?
I believe the question is “Are you an unlawful user of, or addicted to, marijuana or any depressant, stimulant, narcotic drug, or any other controlled substance?” and that would make all the potheads in violation of the law as well. Marijuana users typically use the drug daily, and even if not, marijuana remains illegal at the federal level.
Anyway, I am sure that Biden's attorneys will challenge the constitutionality of the law besides trying to make a factual defense on the grounds of that he wasn't addicted. The unlawful use, if he was using something other than marijuana, may get tricky, but still the question as a whole seems to proscribe status versus any specific act, which gets back to those old 1950's anti-addict laws, which were all struck down.
Today, being under the influence of an illegal drug is against the law, being under the influence of anything legal or not to the point where you're a danger to yourself or others is illegal, but simply being an addict or abuser of drugs is not a crime. In a state like Nevada, for example, they essentially don't even have an under the influence law because it's so hard to enforce it, absent some other crime being committed (i.e. driving under the influence) the police need a search warrant just to gather the evidence (blood test, etc.) to make a case. Driving impaired - Nevada prosecutes. Walking around loaded - as long as the person isn't bothering anyone and is staying away from the high rollers on the Strip - is left alone.