How can you verify the actual size of the black market dollar?
The most important thing is that major operations are not done in this market, obviously.
Also, bizarrely enough the location of all "cuevas" (which is what we call the physical places where the illegal market operates) are well known by the authorities and could be shut down if they so wished. So there is definitely that in favor of the "the government is corrupt" argument.
As for the size: again, major operations -- the kinds that actually "move the needle" -- are done in the legal market. I seriously doubt crypto has any impact in Argentina.
Another way to look at it is that crypto is strengthening the dollar’s foothold in Argentina and weakening the state’s ability to manage their own currency, to extremely detrimental effects.