If everyone was using Silverlight today I suspect they wouldn't be saying the same thing. Instead it has virtually no traction among devs (aside from a core group of hardcore Microsoft boosters), it has little legitimacy, and the smartphone explosion has rendered it dangerous to choose.
If Flash is a relic of the past (true), then Silverlight is a relic that didn't even have relevance in the past.
It sounds like Microsoft is adaptive and pragmatic. What's not to like about that?
It's one thing to suggest, fail and then drop technology. Google does that. Even new Apple does that from time to time. It's another thing to suggest, fail and then keep developing technology in some state of semi-cancellation while backing a completely different approach at the same time: for instance, Silverlight. Right now, it seems like a classic case of throwing stuff at walls and seeing what sticks. That's part of the reason why Microsoft is struggling in any area except for its core business.
But before we laud them for moving away from yet another high-profile flop, why didn't it gain traction? Why was it wrong for the market? Because it failed to learn the lessons of the past. It is yet another not-invented-here, one-stack-to-rule-them-all product from Microsoft. It needed developer mindshare and it was going against an entrenched competitor in Flash.
Why was it even begun, amounting to a massive waste of developer time, money, and opportunity cost? That's the real problem at the core of Microsoft. Everybody's a dreamer, everybody's a star, failed projects pad manager resumes on 1 Microsoft Way.
I find MSDN equally hard to work out for other technologies as well, but at least there are other resources out there, with silverlight sometimes the only mention of a feature existing is on a developer blog.