All these arguments and people who are insistent one way or the other are nice but how about let's stick to the facts as provided by Merriam-Webster dictionary:
gravy: a sauce made from the thickened and seasoned juices of cooked meat
Gravy - Definition and More from the Free Merriam-Webster Dictionary
And please notice that is origin is Middle English and French not Italian.
Now when I was young my mother did start the "Stuff" from braised short ribs so I guess technically she made the gravy by thickening the meat drippings with tomatoes and seasoning etc.
I mean nobody really cares about what it's called. Do they? But I have heard people who get upset when they hear it called gravy. Silly thing to get upset about. Don't you think?