Cause they're only focused on money.
Just a minute: i always put a lot of emphasis on monetization, but on the proccess.
The misconception is at the deep level: assuming that the newbie tries a strategy, he could make some money. But at the very next instant he made it, he would turn obsessed on making money as an atm.
That's belong on the realization that he had made some X amount of money in minutes, while in his normal job it takes a lot more. So he ends up thinkin that it's easy and fast.
The error is a very deep level: what made these money are the habits, actions, etc that created an enviroment BEFORE the result.
So after he turned out in a money-seeker he realized that it's not so fast and easy, and he fall in Shiny Object Syndrome: he start to jump from opportunity to opportunity, achieving less than nothing.
Finally he will stop, but he will think that it's a whole scam the MMO Dream.
But the problem is not the MMO Niche: it's the consistency and focus.
What makes money, big or not big money, is the focus on the strategy itself, the content and of course the monetization but STICK TO THE PLAN!
What makes you failure is the lack of consistency and the lack of focus on the PROCCESS not the final result.
You of course are in MMO Niche to find the paddle of gold at the end of the rainbow, the Laptop Lifestyle, but for getting this result you need on focus on the proccess: which is the amount of habits, actions, repeated day by day for YEARS.
Yes, for YEARS. That's why so few people become IMers full time.
It's not fancy, it's not so attractive to say that you have to work for years, but it's the truth.
With technology, mobile apps, and so on, we're persuaded that everything is at the distance of a click, but it's not.
You need to rinse and repeat a set of actions for years most of the time.
...And call an exorcist to pull your shiny ideas out from your head.