As someone who actually used n900 for a while, thinks it was really cool device, and who developed software for it, I say N9 was a fantasy. Way too little even more too late. This comes back to the cultural issues OP mentioned, there was still too large part of the organization who really believed in Symbian, and on the other hand Meego ended up as kind of punching bag for some "strategic" efforts (like Qt and the Intel/Samsung "cooperation") without enough actual engineering.

> It was essentially Debian running in your pocket. It already had a huge "app store", all Linux repositories.

They dropped Debian as a base and switched to Moblin, which was one of the problems. Also it is telling that you refer the community repos as app store, and ignore that it also had actual proper app store too ("Nokia store"). The utter failure of Nokia store was another glaring issue that they never figured out. Critically the community repos, no matter how awesome, did not support commercial apps in any way, nor did it bring any income to Nokia.

> Polishing this was not that hard, given that they also controlled Qt

Yeah, nope. 80/20 etc.