Well the guy doesn't know how they really do it on OS X.
And yes it is comparing update methods. They need to do what they do in order to deal with some of the bad aspects of how Linux installs packages.
They could ignore that completely and have each user install Chrome in their home directory, but apparently it is easier to write a bunch of code to work around rpm/deb-style package management then to try to convince Linux users to not depend on rpm/deb for installing and updating Chrome/Chromium.
He also seems to indicate that it's not going to be a issue with them on Chromium OS.