Seems like an extremely poor deal for America, was my initial reaction, but on finding out who Paul Whelan is, I expect Griner was just thrown into the deal as an afterthought, since without her it's a direct swap of 2 (alleged) agents of rival states - which seems more conventional for this sort of thing. Although if she wasn't a famous athlete I expect she would just be forgotten about, which would obviously be highly unjust and unfair despite that being how the world works.
Yes, it is hypocritical and yes, it was stupid of her to import drugs into Russia. That said - it is still, IMO, the right and morally correct move to attempt to secure her release. 2 wrongs don't make a right and while her celebrity status no doubt gives her unfair value and an incentive to negotiating her release, compared to the average nobody, and even though there are countless people unjustly incarcerated or with criminal records for bullshit drug "crimes" in the US - these are, for the most part, separate problems that need to be dealt with.
While it would definitely make it easier to represent the moral high ground if Western nations got their own shit in order as far as properly ending prohibition within their own borders first, I think, hypocrisy or not, where it is possible to pressure nations with absurdly punitive legal systems into releasing American citizens (or, indeed, citizens of any other nation with the geopolitical standing to exert such influence) when they have been incarcerated for things that are not real crimes - it is morally correct and just to do so.
In this specific case, of course, I don't really think questions of objective ethics came into it at any point. Griner was arrested because she gave Russia the opportunity to use her as leverage, whereas in more peaceful times she might well have got away with a fine or a slap on the wrist. Her release is potentially on the cards because to America, she is a revenue-generating popular figure, it's both economically and politically likely to be favourable to secure her release - and from Russia's perspective, this was the primary reason for arresting her - to use her as leverage, likely in exactly the kind of prisoner swap that is now being discussed. None of these things are really ethically defensible behaviours, but despite that sometimes the right thing is done for the wrong reasons. I don't know if this is exactly the right thing to do in this specific situation, but if we reduce it just to whether or not it's right to try to secure the release of citizens incarcerated for fucking stupid nonsense by tyrannical regimes - then to me it is right, even if it would not be how things play out for so many other people, or in so many variations of this scenario, and really just illustrates the monumental unfairness of the world as it exists today.