Humor is not discriminatory by definition. It can be, but is
not always discriminatory.

Example:

Q. Why is Santa always so jolly???

A. Because he has the list of all the naughty girls.


Ah, but you just pointed out that "naughty girls" are different. Maybe
discriminatory isn't the right word.....segmenting might fit better?
Someone has to be segmented from everyone else for it to be funny.