My humble opinion on Nexon's path.

Here is a serious question, how is it that no other developer has been capable of creating another 2D sidescroller platformer whatever game like MapleStory?. I'm aware there are/were other games of the kind out there like LaTale and Wonderking but I never got to play any of both so I wouldn't know why they never grew as popular.

I'm assuming it's because most of the players who first played MapleStory were in their childhood-teenage years. As it went by, MapleStory got popular and players continued to play the game. Now that it's been 5-8ish years, the same players are more matured but probably referred their friends and so on forth, creating this sort of endless cycle.

I don't know; that's what I think. I mean, if you play something for a long time, you would figure that some sort of bond would have been established, making it hard for some people to quit.