"Cannabis is a good proxy, states can keep it illegal and not make tax revenue or they can legalize it, control it and tax it."

That should be a great proxy, but regulators have so overburdened legal dispensaries that they need to be bailed out. Illegal sources could have been easily been made extinct or at least sidelined, but are still able to thrive because the overhead to get a license and stay licensed is so immense.

https://www.latimes.com/california/story/2021-06-14/californ...