What does that mean, precisely?
It doesn’t particularly appear that the ConsensusPlusClassic addon depends on automating /who() API calls, which afaik is what was changed.
UPDATE
TL;DR: It works.
So, it seems that this addon does indeed work. Blizzard broke the ability to make automated calls, so there are manual steps to the process.
Reading through the addon-bugs channel in the WowClassicPopulation discord, it seems that there are a couple of ways to manually trigger consensus data gathering using the addon, and that it uses ctrl-T by default, which some locks and hunters seem to have had issues with.
There are suggestion such as enabling the “Send who request on mouse clicks in the world” option, manually starting the process over the minimap button menu, and even making a /run ManualWho() macro.
All of that does make me wonder just how many people would go through the trouble to collect and upload data for the consensus, which would obviously play a major role in the accuracy of the overall data.