Reddit, about yesterday, started to implement a change....
They have the old Reddit interface and then the one that replaced it ("new Reddit") and the current interface you see on Reddit replaced that. People don't like the most recent interface iteration but had the option to go to "new Reddit" or "old Reddit" by vising the appropriate links.
Notably, each newer interface seems to be more stressful for the servers to run. Still, likely a decent amount of folks don't like the newest interface so likely the load balances out.
Yesterday though, they "pulled the lever" and "new Reddit" is no more. (This was announced about a month ago at this link but they only got around to doing it yesterday.) Those people trying to access "new Reddit" are redirected to the latest interface. You have the option to use the oldest Reddit interface or the newest one but not the "new Reddit" one. Since the latest interface seemed to use the most server resources before, it is interesting how Reddit seemed to have their severs overloaded a bit when they made the switchover.
On Reddit, people have been upset in /r/help that this has happened but Reddit will likely continue on with this change anyway. Old Reddit will continue to be supported (at least for now anyway).
Someone may want to know if you are a Democrat or Republican (for advertising, for gerrymandering, whatever). That person may not be able to ask you a direct question like that though (or may feel that you may lie about the answer to such a question anyway).
As such, they likely carry out occasional surveys asking people who are Democrat or Republicans for their opinions on something else. Once they find something else that can strongly correlate your political affiliation with a specific opinion, they know of a new question they can ask someone. That new question should generally reveal what your political party is most likely and they can then proceed with that "most likely" answer.
So "who cares" is those who cannot directly ask you something. They will ask you something else and use that answer to deduce the information they cannot obtain directly.