Maybe IndexedDB is bad. I'm withholding judgment. That's not the point, and your demurral on that particular example should not make you reject my entire argument. WebSQL is not standards-track, period. Whether it should somehow get back on the standards track, let's debate elsewhere.
We could go awry on H.264 vs. VP8 too (I'm not religious), but note how Chrome has best of both worlds, including paying the gangster fee (MPEG-LA license). Not exactly "open".
The minor point for this discussion is that works-in-WebKit happens, but mostly unintentionally or out of rank laziness on content authors' parts. It may even (as you suggest and I agree) provide a big clue-stick to repair a standardization mistake or pox-on-both-houses-try-again situation.
Meanwhile, and this is the major point: works-best/only-in-Chrome looks like an intentional marketing game, backed by a nine-figure budget. Big difference there.