No, it does not make more sense.
Fifty million units, versus five million, and it would cost more, and take longer, to get on that much smaller install base. It in no way makes sense.
Fifty million people are aren't interested in buying games for a console that is about to become obsolete versus five million people who most likely will be looking for a shiny new game for their shiny new toy?
If you release on PS3 near the end of the lifecycle, you get Final Fantasy fans and not much else. If you launch alongside a new console and your advertising is good, you can get the Final Fantasy fans plus people who would never touch a Final Fantasy game because they are looking for a "AAA" experience on their new box.