To me, gravy (unless further described) means a thin brown sauce made from the pan drippings of roast meat, with flour and broth and possibly wine added. It can be beef gravy, chicken gravy, turkey gravy, or any other roast meat (pork, goose, whatever.)
So i don’t really recognize either of those dishes as “gravy”, although i have had Southern white sausage “gravy”, and I’m familiar with Italian tomato-based “gravy”.
And actually, i think any of the three types of “gravy” served on noodles could be tasty.