Interesting, I wonder how that would play out when games can have an autoplay mode, automatically handle certain features (Total War was and is arguably a "complex strategy game" but a single click can autodetermine battles), the mechanics can be simple but the game can also layer a bunch more on top of things for the story (do you really think everybody that played it "got" Bioshock?) and I am never sure what kids can and can not understand/make sense of (beyond the "children are just smaller, less well mentally formed adults" concept being very wrong). Now there is certainly a merit to your ideas and I would not mind seeing something of it come to pass but there are a lot of questions and problems that would need to be addressed from where I sit before the full version of what you say could even consider coming into effect.
Thanks for your input! It's true that it's very hard to know how it would/should be applied, and which criteria determines what. What I basically got the idea from is board games. They often have recommended minimum ages, based on the difficulty level of the questions in quiz games, complexity of the rules etc. And as always, there are exceptions, that's why I like the term "recommendation", it's never set in stone. Another thing that made me think of this idea several years ago was actually Zelda: Ocarina of Time. Here in Sweden (or all of Europe to be specific) on the box, it says it's from 3 years old. An average Swedish 3yo wouldn't what to do in the game, since we don't learn English until we're 7-8 years old.
That kids aren't "just smaller, less well mentally formed adults" I know. We're often discussing all kinds of subjects regarding children's mental development in GCP groups (gifted children programme), and at such a young age, mentality is so very individual. (Just as individual as in adults, really, haha).
Now, 3 year old is maybe pushing it. But when I was between 4 and 5 years old, I played Megaman 2 a lot! I didn't beat it, but eventually I got to the second Wily stage. (with help with the instadeath laser). But I could pick it up and play it, and have fun trying to go through the stages, trying to survive. I also played X-Com when I was 7. Sure I had fun with it, but I mostly built a base for all my cash, pressed the time settings and watched the earth spin. Then Aliens attacked and game over. I had fun, but didn't play it as it was intended (barely played it at all). Maybe it's too advanced for an average 7 year old.
The same goes for Total War, even if there's a single click battle thing (never played the game). The concept of war strategies, troops, defense, economy etc. might be too much for an average kid to play the game somewhat properly.
Again, that's why I think it would be a good thing to just recommend an age, along with information on the content.