I utilized EDHRec's top 50 creatures associated with a commander for every single legendary creature. Then I tabulated how many times each creature appears in one of those top 50 lists. I then cut that list to the top 250 most frequently occuring creatures.

I'd love to give you an example. Solemn Simulacrum appears in the top 50 creatures on EDHRec for 841 of the ~2500 legendary creatures available to be a commander. Eternal Witness appears 377 times in those same top 50 lists. Braids, Arisen Nightmare, appears in 168 of those top 50 lists. So I took whatever the top 250 creatures were appearing in those lists, and then ran the same targeting parameters that I ran for the other pages, against just those 250 creatures.

It sure will! this data doesn't take into account how popular a given commander is. If 10,000 people have Zedruu the Greathearted commander decks, and 5 people have a Teferi, Archmage of Zhalfir commander deck, and they both run Mulldrifter, but Teferi doesn't run The Reality Chip, then Mulldrifter will have 2 instances, and The Reality Chip will only have 1 instance, even though the Reality Chip sees probably 2000x play.
Once I can develop a more sophisticated way of accessing EDHRec's commander data, I would love to add some additional analytics, but for the time being, this should give you a good idea versus a random sample of commanders. If this is something important to you, or something you'd like to see, please let me know on the contact page!