I think part of the problem is that some people have gotten too politically correct, and try their damndest not to let anyone do or say anything that might have a snowball's chance in hell of offending others. It can be carried too far.
At the same time, there is a growing contingent of people who are so sick of political correctness that they intentionally try to rile up those with delicate constitutions, just so they can fire back with "get the fuck over it!" retorts. Basically, there are two extremes.
Meanwhile the average person uses common sense, and determines for himself or herself what offends them.
It was a sad fricking Christmas Eve at work when I was told to take a Santa hat off because it might offend someone who didn't believe in Christmas. I said, "That's okay- Christ didn't celebrate Santa Claus either". The joke was lost on the HR rep, and I got a "note to file". When asked why I made such an inflammatory comment, I said "I didn't know good cheer was offensive- and I'm Buddhist and still enjoy Santa".
Okay, that went off on a tangent.