Fatbike tire footprints? I am curious if there are any empirical experiments, or theoretical computational results, comparing the "footprint" size of the various fatbike/29er/mountain bike tires?

There are lots of claims about how this tire can get through that material better than this tire.  But, at the end of the day, the reason for these differences is the size of the tire makes with the surface of the road/trail/snow/mud/sand.

I get that these things change with tire pressure as well, so feel free to add that as a variable.   I weigh 180 pounds, so that's what I'll be using if I do this experiment this weekend.

My lack of results in Google may be due to my unfamiliarity with the right terms.  If there's a better term for what I want, I'd love to know that as well.
There are more variables that you are missing.  Rim width is also a factor as well as the tire "setup" itself (tubeless or tubed).  So all the variables you would be looking at are tire width and size, rim width, tire pressure and wheel setup (tubeless or tubed).  For any or the data to be meaningful, you'd need all of that data.  Generally you will get the widest footprint/contact patch by riding a wide tire on a wide rim at low pressures with a tubeless setup.