I think the LG is awesome for 3D and not so good for 2D. I like the others for 2D.
Technology moves quickly though. Look at TV history. What was unheard of yesterday is happening today. You can expect that to continue.
3D TV is in it's infancy. A relatively new concept for consumers.
Some day there may be a 3D display that doesn't require glasses. The pixel size would have to be super small (a few microns). Possible but unrealistic by today's standard.
"Is 3D TV all that necessary?" This is like asking whether or not sushi taste good. It's not for everyone but if you like it, enjoy life!
In the not so distant future, I imagine, good quality 3D will be a standard feature on the cheap models.