Whenever you feel the urge to use, or see others using the term political correctness, try mentally substituting it with behaving respectfully. The exercise can be enlightening.
That doesn't seem like a useful exercise because political correctness does not always equate to behaving respectfully, even if there is overlap (i.e. most respectful behaviour is politically correct and vice versa).
I could just as well suggest you mentally substitute the phrase helping the needy with kicking puppies whenever you encounter it.
For example, mocking masculinity/men, white people, Conservative people, etc is all "politically correct". I would not call it respectful to call Trump voters deplorables or to belittle issues that men face, but it's certainly not politically incorrect.
I think I see what you mean, but in my experience, this is not how most people understand or use that term. Wikipedia backs me up on this:
The term political correctness (…) in modern usage, is used to describe language, policies, or measures that are intended primarily not to offend or disadvantage any particular group of people in society.
I could just as well suggest you mentally substitute the phrase helping the needy with kicking puppies whenever you encounter it.