I'm not surprised that major companies are reticent to market, advertise, and profit off a game specifically about starting a drug tycoon business, and I'm a strong advocate for legalization of marijuana (where it's legal in the state that I live in, and I have a medical card). I also think it's a false equivalency to say "Grand Theft Auto and Hitman are sold, those are about stealing cars and assassinating people -- two illegal things!" but they miss all of the context of those games, and that both of them are about much broader subjects than the titles of the game. There have been games that have gone too far in the past and game publishers/service providers have been reticent to sell them, and not because of the illegality of the thing. Personally, I think that GTAV went way too far in many of those missions, but because they're several small missions in a much larger game, and the game has such a large cultural cache, it's still sold -- although GTAV was widely criticized for those scenes as well (I'm talking particularly the torture scene, it's my most hated gameplay segment of just about any game I've ever played, completely pointless, and because Rockstar presents it as 'satire of the American government,' or what have you, they think they're putting one over on The Man.)
It's not just the quasae-legality of the, largely harmless, substance, for instance I think most game companies would be similarly reticent about a game called "Opioid Tycoon," even though opoiods, a regulated substance that millions of people use responsibly, can be legally prescribed and obtained in every state. It's not just the federal illegality of marijuana, but that a game called "Marijuana Tycoon" leads critical people to think that Microsoft, Sony, Nintendo, and others, are profiting off of a game where players become a tycoon of marijuana which is still a sensitive subject even in places where marijuana is legal (like where I live in the United States). There are other legal "Tycoon" concepts that would be controversial as a videogame and I think major game publishers and content providers would also be cautious to have on their networks, I'll let your mind wander. For a softer topic, I think something like "Tobacco Tycoon" or "Cigarette Tycoon" also wouldn't go over well, both are legal, and the games could explore the depth of cigarette regulations or something, but I don't think it's something most companies would want to attach their name to on their sales platforms.
It's consistent for Valve to allow the sale of this on their platform as they generally take a content agnostic approach (which is also why Valve often has really distasteful content on there pretty often), but Microsoft, Sony, Nintendo, etc., I'm not surprised. I think if marijuana became federally legal in the US they'd be less apprehensive about it. Major platforms also do not allow advertising for marijuana products (which even as a legalization advocate, I'm thankful for because I can only imagine the sheer enormity of how stupid those ads would be).
