You misunderstand. It does not matter who started the trend and for what reasons. Blizzard's decision to go with cartoony art was based on appealing to the widest audience demographic possible and catering to the widest range of computer systems at the same time, i.e. maximizing the number of potential customers.

After that, and the massive success WoW enjoyed, it became really irrelevant who "did it first". It does not matter anymore.

Concerning games the OP mentioned, however, I must point out that Settlers were always cutesie and I played every one since the beginning of the series. It might have been hard to notice the big blue eyes on those old 640x480 resolution monitors, but they were there.

So don't be surprised - I doubt we'll ever see a Settlers game where you can impale your citizens on long wooden poles and stake them along highways to produce a movement bonus.

That said, I think the OP's problem is that he wants to play the wrong type of game for his tastes. If anything, graphics in games (at least those proper games on PC which require having a brain to start) tend to go for more and more realistic presentations. If cartoony graphics bother you, you can always play games meant for a more mature audience, there are plenty of them around. Now, if TES V or Fallout 4 go the cartoony way, then I'll start to worry. Until then, kiddie games will always be catering - for kids.

P.S. A good example of a realistic graphics MMO is Vanguard. I know of a certain monster in that game which actually wakes certain phobias in some people to the point where they avoid playing in the entire area. I am sure you can see why a company primarily interested in making money would consider that a bad design choice.

But WoW did start the cartoony *trend*. Because WoW is a trendsetter, like it or not. There is a whole spread of games which look and play the way they do directly because of WoW, not because of whatever game happened to "do it first".

Its like that in many other game genres. For example, when you think which game influenced the "point and click" adventure fad in the 90's, games such as The Secret of Monkey Island come to mind. Other games, which were in my opinion equally good, such as the Maniac Mansion which appeared a year before - do not. Not to mention games which "did it first" but are so obscure you have to look them up on Wikipedia because no one but the most enthusiastic gaming history aficionados remembers them.

Or first person shooters, when you ask which game started the whole genre, most people will tell you Doom, or Wolfenstein 3D. No one remembers, or cares for Maze War, which actually is the first "who done it".

Give credit where credit's due all you want, but the fact is that its not enough to just do an idea, you have to do it successfully. And no game so far has surpassed the success of WoW.

Just FYI, I hate cartoony graphics.

I never said Legend of Zelda was obscure. But it does not factor in the current discussion. The OP asked how come so many games (although I do not think there are that many) are cartoony. Obviously, complaining about the "cutesy" style of Sims or Mario, or any kind of "non-serious" game is kind of ridiculous, since that style fits the theme. Therefore I assume the OP is complaining about inappropriate use of such art styles, i.e. in games where the genre or content implies seriousness and yet is graphically represented in a way which contradicts that.

So if we ask ourselves why would someone make such a game, I claim that its because that someone is a clueless manager who has no idea what makes a good game and thinks that if the game looks like some other mega successful game, it too will be prosperous. Now, you may claim that Zelda was a successful example of a cartoony game, but I counter that Zelda is much like Mario - that is its not really meant to be that serious.

WoW, on the other hand, has a very epic, very serious premise, despite the gnomes. And here we have an example of a serious story mated with cartoony art style, resulting in a very successful game. So when I think which game is more likely to have influenced any later game which tries to join a serious premise with a cartoon look, I think of WoW, because that's what it did. Zelda didn't.

In fact, and I may be wrong here, but I can't think of any other game which reaped such success and has had as much influence as WoW when it comes to mixing of seemingly contradictory art styles and genre. Mostly because usually, it doesn't work. In fact, even WoW, at least initially, didn't go overboard with the style and silliness, limiting it mostly to exaggerated equipment, few side quests and zigzag style of architecture, because trying to do such lowpoly models in a realistic fashion would just make them look like crap (let's not forget the lowres textures and the general lack of 3D essentials such as bump-mapping).

So this discussion is not about which cartoony game was the first, or most popular, its about how come there are absolute horse manure games in existence which try to do a Sesame Street styled hack'n'slash dungeon crawler. I say its because of WoW. You may have a different theory.