The thing about growing marijuana by cartels in California is only economically viable because you can sell it illegally in other states. e.g. you grow in California, where you're going to get less charges if caught, then you export it to states where it's still illegal so you can sell it at black-market prices, without having to deal with border security.
None of that implies that if you legalized it nationally that cartels will thrive, because the whole point of those operations is to exploit the difference in legal status between different states. Read the article, the sites in California where it's grown for cartels are all illegal growing sites, and that's all so that they can ship it out of the state to other still-illegal states, without their being any paperwork in California. Legalizing it nationally removes the basic profit incentive here.
Cartels = maximum profits for minimum work. When you legalize things, the free money dries up and normal business become more efficient than hap-hazard cartel operations. Cartels just aren't as efficient as regular companies, and that's sort of the point: by focusing on inefficient markets, you can do less work yet make more money. That's the basis of why cartels do the stuff they do. e.g. regular companies make cigarettes, and regular companies make alcohol, and cartels don't have a big hand in either of those markets, because when you legalize a business completely, then the inefficiencies get driven out of the market. A cartel exploits illegal markets purely because they're inefficient, thus you can make high profits for low amounts of work. e.g. cartels don't sell drugs because "lol, drugs" they sell drugs because the profit margin is high vs the amount of effort put in, and that profit margin is because they're illegal.
If you federally legalize marijuana, then it becomes no more attractive to organized crime than cigarettes and beer are. e.g. cartels could produce their own cigarettes and beer, but there's just no incentive to do that, because the effort to do so is the same as the effort to just have a regular job. It's the same with marijuana. If marijuana was legally treated like beer is, then the market around it would adjust the pricing so that it's in line with other legal products of a similar nature. Cartels just couldn't compete with licensed above-board growers who are selling to licensed shops through licensed distributors, any more than you'd be able to start your own home-brew company and out-compete Budweiser.