[mythz]

If Google is developing Flutter so they can be more productive at developing their own flagship iOS/Android Apps than the chances it will be discontinued is quite low.

So whilst it's reasonable to hold off until they adopt it themselves and use it in their own deployed Apps, but once they do I'd be more confident in a commercially-sponsored Google project than an Indie OSS community led project. You just don't hear about the thousands of OSS projects being abandoned because they're from multiple Indie authors.

But I wouldn't trust a project with this large a scope without mega corporate backing. But I'd agree that if Google stops committing resources to Flutter than it will die despite being OSS'ed since it's too big to maintain without a well-resourced team.

Not all Google projects should be considered equal, if adoption is low and they don't have flagship Apps, high-profile initiatives or cost center's backing/funding the project then the project's future would be at risk if it doesn't become successful, but any project that is successful, has adoption or paying customers are very unlikely to discontinued, e.g. Angular, Firebase, Google Cloud Platform or any of their popular platforms, i.e. Chrome, Android, YouTube, etc have zero chance of being abandoned.