Yes, most of the ones in my region of the country that were built a few years ago are the 120kW kind, and you're in Utah, so I would think it's some of the same ones you use.
Pendleton, The Dalles, and Baker City Oregon
Boise and Twin Falls Idaho
Tremonton and Salt Lake City Utah
Winnemucca, Elko, and West Wendover Nevada
They were built before Tesla switched to doing the 135 or 144kW style.
I don't get why you would say the number of them is "dwindling", except that the % of the total is "dwindling" just because all of the new ones being built now aren't 120kW kind. That seems like their acceptable minimum, so they don't seem to be doing any retrofitting or upgrading of those.