Yeah, if you wanted to truly unify all the remote controls... Right now, it's just the only practical reason you'd Chromecast something from Netflix to your TV rather than using the TV's built-in Netflix.
Another possible advantage to the Chromecast route would be use of a hardware keyboard if your phone/tablet has one.
But some TVs have this already built into their remotes too.
Yup, anaglyph has existed since before I was born, and I played with 3D visualization on an SGI workstation in the very early 90's.
Remember WebTV? Hehehe... Convergence took a few rounds, but it finally arrived... sort of.
Chromecast and Second screen is the next evolution. After all, Netflix invented DIAL.
Hey, those Watchman devices might come back... I have to admit, I kind of want a Galaxy Gear even though it doesn't do video.
Don't laugh...Not only do I remember WebTV I have a neighbor who still USES IT! I tried to get them to switch to a GoogleTV but they were not technically up to it! LOL
3D is great for content that is shot for it. But most content in 3D is shot in 2D and then converted via Software..No Wonder people get headaches watching it! LOL
But back on topic...
I think the chromecast is a great initial first step. If it does well (seems to be doing that) I believe future versions might add some of these features in time.