Aside from the unpredictability/reliability/stability factors of running this over a server connecting to thousands of machines, feeding information back and forth... there is also the issue of having to write this program probably from scratch or something close to it to run comparable to the PS2 version.
The other thing is (and I'm guilty of not keeping this in mind myself) as generations pass, demands of development increase as technology becomes more complex. Not saying it was easy for those working the PS2 game to make it happen because they certainly had to have a lot of challenges, but it certainly will be harder now to pull off the same type of task. If you have multiple cycles to work it, it's not as big of a deal because you can chop away at it slowly. Even so, it's still going to be tougher.
Aha!
This was exactly my point. I would've thought that anybody today clamoring for online franchise would've been all over a feature like Franchise Live Opponent. In Madden 07 for 360 (and probably PS3 but I don't know about all that version offered) You could take your franchise, connect online, and then bring in a live opponent to play you in your franchise. It also allowed you to use custom rosters, so this could be considered a sort of bare skeleton/test pilot of online franchise. Madden 07 sold about 2 Million copies on 360, and yet to be honest I've never actually seen much discussion about this feature outside of some passing mentions here and there.
When I think hardcore, I think of people like the OS crowd who come here to discuss and dissect every minute detail of the game. These people play the game looking for deep value in modes, functions and options, and authenticity of experience that stacks up to its real world counterpart. This group is small compared to the casual.
When I think casual, I think of people who don't come to places like these to discuss Madden. They don't care about the minute details of the game, nor do they care to discuss them. They aren't looking for deep value as much as they're looking for quick gratification, and finding the newest wrinkle (glitch) to beat their buddies, and by association to that, aren't concerned with authenticity of experience.
Now to me, the tourney guys (and this is probably not entirely fair, but Madden Nation just ruined it for me) are just hardcore cheesers, lol. They carry all the attributes of the casual, except the play the game a lot more.
I think you fall into the hardcore group because that's the type of player who would be most interested in this. A franchise going online and hammering it out with multiple people over a concrete 17+ week schedule just doesn't fit the mindset and behaviors of a casual player. There is too much obligation there for a casual to stay connected with this. Making trades, doing drafts, signing free agents, keeping a full season schedule and sticking to it... these aren't casual behaviors.
Remember Capn, the first step is admitting you're hardcore