You are implying no ecosystem = no future. But if that'd be true, how comes android made it? And iOS? They didnt happen to have an ecosystem when they started as well. Nokia had Ovi Store, at the time the biggest (symbian-based) ecosystem. All the prerogatives for an ecosystem which would have included Meego devices were there.

Also, keep in mind meego was supposed to have a big rollout, whereas Maemo were all experimental devices.
From my perspective, there's more technical issues here:

a) the skitzophrenic qt / meego split
N9 was hailed by nokia for Qt, *not* meego. But meego was *there*, on the n9, and working just fine! I guess this was the best patch Nokia could come up for the to-be ecosystem solution with symbian (qt "portability"). This confused message disoriented developers quite a bit IMO. Throw in the complexity of the platform api's (a.k.a. linux) on top, the non-native look-and-feel of the Qt Apps vs the native-looking Meego apps, and you have a beautiful disaster. All the tools were there for both worlds (qt & meego). but which one to use? no clear development path or guidelines (cause of marketing reasons as they had to push qt!), no clear toolkit choice. I mean, the phone was sold as a MeeGo Device, but Nokia was pushing the Qt toolkit for it! What a clusterf*ck for God's sake!
Developers had been promised " no more two stacks!" by Nokia, instead they got two toolkits . They were promised "a linux-based device", but in reality they were meant to build Qt-(and aegis) based applications (keep in mind meego was also qt-based)...do you see where this is going?

b) the idiotic rollback of the marketing, by denying the product to be actually shipped in key countries like US. Nokia could have betted more on the UI (which is what the n9 excelled at). Yes, the development experience was flaky, but come on, the first iphone was very limited too! Bottom line they had a product, with a valid UI, which they didnt trust in, and got cold feet. And thinking about point a), no wonder I'd say! It would have taken a leap of faith and a full commitment, but in reality, instead of jumping in the cold and dark waters, Elop stayed on the platform, and burnt down with it.

And about app support/sustainability in Jolla, speak for yourself. At least quickbar has been working fine for many releases now, with no need for updates in quite some time (im surprised myself) - in harbour. I would not be surprised for patches not to work the same way.