It's flawed research ...
They suggest that the 'top' sites don't use these features because they aren't required, but the truth is that they don't use these features because they are still trying to support ancient browsers which predate these specifications coming about.
So as a result they propose some of the most useful developments which came about to make browsing faster, more secure and reduce battery drains. Developments which are meant to rid us of the likes of ActiveX, Flash and their ilk? Development which are meant to reduce page bloat.
SVG images are much smaller and much higher quality, you only need to serve a single version not a range of different sizes.
Canvas provides an alternative to Flash (which is way more insecure).
Websockets allow for 'push' to the browser, eliminating the need for polling - reducing bandwidth consumption on mobile devices.
Granted some of the listed features are probably unnecessary but certainly not all of them.