I like to compare it to beer rather than tea. You can make it for dirt cheap, but based on some research months ago, growing truly quality stuff is an art. So, like beer, I expect there will be Coors MJ, and there will be Microbrewery MJ. The former a baseline of reasonable quality for the price, the latter far nicer than anything John Doe can grow in his basement, probably complete with hydroponics and sophisticated monitoring.
But for the time being, it will be expensive because of risk, ramp times, capital investment, etc.
I don't know where you got your information. Yes, hydroponics and growing under artificial light is pretty hard - but farming MJ in the open is easy, the thing grows like grass.
But for the time being, it will be expensive because of risk, ramp times, capital investment, etc.