I'm not here to "convince" people to use Dart. That will only happen because of it's utility to developers, and I'm more than fine with slower organic growth if it develops more from actual problems being solved, and less from hype. If anything there's a ton of anti-hype around Dart, so it has a lot to overcome with some people even if does address their problems. Such is life.
I'm pretty sure there will be such an explicit commitment to Dart communicated externally, but since I'm speaking for me, and since the question at hand had to do with what would happen _if_ Dart were canceled I addressed the hypothetical situation. Maybe a PR departments would have danced around that and simply said, "we're committed to Dart. Next question", but I'd much rather dig in say that we're committed, but sure, "what if". To me that's a real discussion, not a rhetoric, not a pitch.
As for my tone, can you imagine what it's like to have the company you work for called "evil" because they shut down a RSS reader or move away from using XMPP in their chat app? Or that you can't rely on Google because of the Reader shutdown, or the price increase on App Engine when it came out of preview. I hardly agree with every things Google does, but the hyperbole surrounding it is incredible. Not every product that any company makes will be successful, not every product can be kept alive indefinitely. Google receives an inordinate amount of flak for it's changes, mainly I think because we have so many products that it's easy to keep seeing a small fraction of them change it's still seems like a lot because it's all under Google. Meanwhile there's multiple instances a day of some other companies products changing, or shutting down, or being bought to be shuttered later, but because they're spread out over many brands. The recent constant chime of "evil" and "unreliable" is so often drawn on really warped and rushed comparisons that don't make sense if just a little thought is put into analysis, so yes, it gets really old, to me, personally.
Not only that, it could cause a "the sky is falling" perception of communities like HN. This is a real concern of mine because many times there are legitimate points here and several of us like to represent them back into the company. If HN reflexively interprets everything that Google does as evil and bad, it becomes harder for the Google members of the community to go internally and say "this isn't being received well, is there room for improvement?". We haven't reached that point yet, but it's something I worry about. The reaction to the "no servers on Fiber" rule is the type of thing that several of us try to represent back to the company. I, and many Googlers, respect the hell out of this community, but the more ridiculous the FUD and conspiracy theories get, the more the reputation erodes. I don't want to see that happen, so I actively combat it when I can, by trying to dispel the falsehoods, and also by chiming in when I agree with some of the negative sentiments. But yes, it gets really, really old.