Whatever arguments existed 20 years ago for simplifying the terms used for turning the transponder on can’t possibly be relevant any more. Of all the things a simmer has to know to succeed on VATSIM, transponders aren’t going to be a massive issue if we name it a bit more appropriately.
Does a new member desperately need to know the difference between A, C, S, and TCAS/ACAS settings? No, but why should we start off by making them think the transponder’s altimeter readout has any bearing on identification?
We don’t even have to do more than renaming the client buttons from “Mode C” to “Mode A+C”, “Mode A+C+S” or even “Transponder On” (yes I know it can be on without subsequent modes active, just spitballing here) if we want to keep it simple but not blatantly wrong.