They probably don't want to support it, and/or suspect they'll have a higher return rate or higher support costs.
The N9 really feels like a "we have a contract with someone that says we have to release this, but not how" kind of device. It's as genuine an effort as a "sorry" from someone who was ordered to apologise by a court ruling.
I was really looking forward to Maemo, but when the Qt-to-GTK switch hit things started looking black, then the MeeGo trainwreck pretty much killed it well before anyone officially gave up on it. A smartphone platform with two incompatible changes in early life and a first handset with a dead-ended platform is NOT going to be attractive to devs. I'm just amazed it was released at all.