"It is what it is"? What is your view on that quote?

I personally dislike it when people say "no problem" and I sometimes challenge them by asking "what if it was a problem, what then?", but the result is rarely worth the effort. As the philosopher Bertrand Russell put it, "it isn't things that bother us, it is our ideas about them that bother us". Therefore, while you do not agree with how people use the phrase "it is what it is" when it isn't appropriate, or you do not like their viewpoint that things cannot be changed or are better left unchanged, you cannot change the behavior of others. Because you cannot prevent people from using that phrase around you I suspect you will not change yourself so you will continue to be annoyed by it. You could challenge people who say that with something like "your opinion is not equivalent to reality", but that won't earn you many friends. Therefore it is indeed a problem that "is what it is".