How long has it been since you heard someone say, "What are you sore about?"
Unless it's a physical therapist trying to figure out what's up with your shoulder, you don't hear that phrase anymore, unless you're watching "Leave It To Beaver" reruns, where someone was always saying, "Gee, don't get sore about it!"
But no one seems to say "I'm sore" or "You'd better lie low...the boss is sore because you stacked those cartons in the middle of the storeroom" anymore. We say, "I'm pee oh'ed," "the boss was pissed," or, "Earl was kinda irked (or vexed, or miffed) the other night because Ralph ran over his surfboard."
We save being sore for when we need to see a doctor. We can have a sore shoulder or a sore back, and there's a cure. A sore throat is often self-inflicted, or the result of a cold, and will go away in two days (longer if it will get out of work or school).
Ever notice that the very people who don't want to show their high school graduation photo are the first to say, "Hey! Look at this sore on my arm! Do you think it's anything to worry about?"
There are sore points, like things you don't want discussed at dinner if you know what's good for you, young man. These can include the fender of the Dodge (and what happened to it), why the family is not wild about cousin Leon dating that woman from down the road with the bad reputation (the woman, not the road, has the questionable backstory), and that algebra test that just about everyone flunked except for the brainiacs.
Flunked? That's another word no one uses anymore! You could bust your britches looking for the last time said it.
Who says bust your britches these days, anyhow?
I have an idea. Let's get all these words that no one says any longer and we'll save the list on a floppy disk.