I wasn't trying to debate how the uniqueness is calculated, you're absolutely right on that, and other sites like creepjs do the same, but I think where the eff site is a tad misleading is in how it presents their "just how unique AM I" part of the results, because they only have their own collected data to compare that against.
Sadly I think even disabling JS entirely would take away so much "blending in" that it still wouldn't be hard to uniquely fingerprint a user without it. Even CSS (without JS) and standard HTML tags like "picture" can be used to fingerprint now.