That's all really a software issue. The iPad Mini allows you to hold it even with your thumb touching the screen and it works perfectly fine, for example.

http://www.slashgear.com/ipad-mini-thumb-rejection-technolog...

If google integrated that kind of thumb/holding hand rejetection to android (since most android manufacturers seem too incompetent to do it themselves) we could absolutely see an era of bezel-less devices that works fine.