Then why do developers like Larian Studios bother with Mac versions of games at all if the landscape is so dire (they are for sure not doing B and C)?
Because it's free lunch. They're using their own engines, which are very dated but multi-platform (how exactly would require some research) which allows them to push out a macOS version at very, very low cost. In return, their games look very dated visually when compared to other modern AAA games. And graphics are a major seller not only for games, but also movies. The more realistic they look, the more attention will be drawn.
In theory you could do the same with Unity/Unreal based games, do basic games with "standard" graphics. But that's not what most AAA studios do. They want a title to be as polished as possible, that's why we also see graphics/performance patches and updated/optimized drivers for games. And the more complex it gets, the less likely a port with Unity/Unreal gets as well due to cost. Just look at all the assets/scenes in the official stores that are only running on specific platforms and that stuff is nowhere near the level of what AAA games do. And that is "click to buy and use" stuff only. Just look at all the other stuff that should work multi-platform, but is not:
https://github.com/Unity-Technologies.
If those were my options (they aren't, there's PC/console), I wouldn't even become a game developer then. I don't care that much about money. Why would I want to be scummy and exploitative if I can, you know, not?
Good thing you're not a game developer then.
The times of "lets make a game, because it's fun" are over. We did that in the 80s and 90s. But we also made games back then to learn things. Games were often made by a single person or very small teams. Look at AAA gaming today, sure people still have fun making games (at least some), but games are green-lit to make money above anything else.
Sure, you have PC/consoles as well and you can develop for those. We've been going in circles here... if you do optimized PC/console then how much is a Mac port going to cost you and will you make that money back from Mac sales?
Sure there are cases such as the above Larian Studio games, which visually look poor, sell in quantities of "ok-is numbers", largely due to a 25 year fanbase in the case of Baldurs Gate. How many copies do you think would a Call of Duty sell if it would be so technologically dated?
In other cases like the Anno games for example it's historical (no pun intended). These are not demanding titles/engines, at least not graphically. They've been using their own engine in the past, Windows only, then evolved that engine, sometimes even rewrite it, but based on their experience. macOS is not on their list, the solution is crossover/parallels here.
In the end, it's all about money. And if developers can actually make a ton of money by bringing games to macOS, they will. They won't rely on "x Macs sold, so in theory we could make y $ with it". Hard facts only for them.
