React Canvas author here. I outlined some of the reasons why it is not always the right answer: http://engineering.flipboard.com/2015/02/mobile-web/#Practic... On Flipboard we use DOM where appropriate for text input and areas of the application where performance is less critical.

And to your point about accessibility: https://github.com/flipboard/react-canvas#accessibility

You are correct that the DOM just works. But we need a better option on the web in order to achieve the kinds of experiences that people have come to expect from native applications. The hope is that by pushing the browser beyond its limits that we can make progress in this area.