It makes more sense to me that east-coast schools would show an artificial advantage on "revealed preference" type rankings, because more Americans live closer to the east coast schools. They're more "locally" well-known, you're closer to home (okay, a disadvantage for some), etc. I'd expect them to benefit more from hype than Stanford would.
And they're older and have had longer to work their way into the culture. Many of the eastern ivy league schools are older than the USA. Some are even older than the state they're in (in the east, unlike in the west, states are often a little older than the USA itself, rather than a litlte newer)
Stanford certainly beats Yale in CS quality both in terms of peers and instruction.
I have significant experience with HYP, less-so with Stanford. I don't think I am a naive audience, I know many people from these schools and have attended classes, either due to being a student there or online videos in the case of Stanford & Princeton.
True, but CS isn't everything. Stanford is definitely much more of a tech school than Yale.
I'd never have gone to Yale because it was a poor fit for my interests. That's different from being a poor school. Overall school quality is less important than fit. Given my interests, I would have pick Stanford over Yale (and in turn pick Caltech, CMU, or Georgia Tech over Stanford).
That said, Yale is a phenomenal experience. It's very academic in the classic sense -- deep, philosophical discussions, and thoughtfully exploring topics in a way that's increasingly rare in the fast-paced elites. It gives a lot of what people assume they'll get out of a small liberal arts college (which is different from the reality; most small liberal arts colleges are expensive and horrible).
I have little knowledge or Princeton. I know both Harvard and Stanford in great depth.
A lot of the elites are hype-over-substance, and it's often hard for a naive audience to screen out which ones.