Why are there no MMOs for Xbox 360?

I am a big MMO fan and wonder why there are none for Xbox 360. We can clearly see that Xbox 360 can support online play (MW3 for example) so I am curious why there are no true MMOs for Xbox 360.

Does anyone know why? Are there ever going to be MMOs for Xbox 360?

The console is dated big time. I don’t know a single person who still uses that console. Not to mention, this deals more with server load. Back then, only a set amount of people can be on a server at one time and the game you mentioned (which is also old at this point) allowed a max of 16 per lobby I believe.