It is not even close to being all but legal in California. Both the state government and the federal government can and will arrest people for growing on a large scale.
Tobacco prices would skyrocket if tobacco growing was as “legal” as it is in California.
Of course it is. It's readily available in any number of dispensaries, there are countless home-growers with growing cards producing potent, high-quality dope and getting caught possessing personal use quantities won't even get you a ticket. I lived in Southern California most of my adult life, bought and smoked my share, and know more heads than I can count (including growers). Not of one of them has ever spent an hour in jail and nobody ever has even the slightest problem finding it anytime they want it.
It's as close to legal in Cali as it is anywhere in the country. When it's truly "legalized" for purposes of taxation, that's when the serious enforcement starts and CAMP helicopters start flying over residential neighborhoods and doors start getting kicked in.