I would guess it happens more than we think, but it could definitely look like brands have an inherent advantage even if they don't.
What I mean is when I look at the big brand sites they generally have the latest user interfaces, top notch design, the most up to date or close HTML, the best or very very good organization and a bunch of little things deep pockets can probably afford to do easier on a site than most people, so I personally think he's telling the truth when he says the advantage isn't brands in general, but with deep pockets comes the ability to be all over things others may not have time for, make time for, or be able to afford and when the difference in "scoring" between 1 and 11 is probably .1% or less the little things that "don't count for much" can make all the difference in my opinion.
Another way to say it or look at it is: There are 200+ ranking factors using 200 as a nice round number, if 190 are equal and the brands can hit 10 of the time consuming or expensive or seemingly unimportant factors just a bit better who wins the tie breaker the site with the deep pockets and the teams of people working on them or the site with one or two people who just don't have time, cash or maybe even the knowledge to do the same thing?
Things like that custom server making a site just a bit faster the brand likely has instead of a shared host. The HTML5, schema.org, ajax implementations that can make a site a bit more focused or understandable to an algo. Possibly the 5 (or however many) different designs or flexibility of design for different screen sizes that's time consuming and difficult to implement but generates a slightly better behavior from a certain sub-set of visitors.
There are so many little thing they can do better based on the cash they have to spend they might not have an inherent advantage but at the same time I think they definitely have an advantage simply due to the level they can afford to build a site on where many cannot.
So, do they have an inherent advantage based on name? I sort of doubt it.
Do they have an advantage on depth of pockets and what they can put into a site over most people? I don't see how they couldn't.