FM is awesome, and the people who work on it are awesome too. I know most of the guys (since I've worked with SI from 2004 through 2006, for those who do not know) and they have incredible skills & knowledge.
Here is the difference between OOTP and FM:
FM simulates Soccer, which is incredibly popular in Europe and other parts of the world. And simulation/management games are incredibly popular in Europe and have a rich & long history. The result: FM ships over a million copies per year.
OOTP simulates Baseball, which is incredibly popular in North America, parts of South/Middle America and some Asian countries. Simulation/Management games in these regions are about as popular as Curling action games. The result: OOTP sells a tiny fraction of the volume FM does.
That's why SI employs (my estimate) 50+ people, and we only employ a handful. Enough said.