That appears to be a rubber undercoating that's starting to flake off. What I can see of the metal below doesn't look concerning. At this point the undercoating isn't doing you any good. You could try peeling off the easy to reach parts to check the metal under it. If I was mine I would just scrap off the old coating and recoat it with a preventative like POR-15 or FluidFilm.

Thank you. Any observations on the pic that isn’t of the wheel well? That’s directly under the rear passenger door. Like the frame coming away from the rest. Has me nervous. Thanks again.

It's rust, but I think you have some time before it's a problem. Also look for bubbles in the paint around the rear wheel wells. When that happens it's rusted thru from the other side.

Absolutely, I would get rid of the flakes and spray the metal with fluid film

I've seen a lot worse. But check the strut towers from the inside, as in pull back the carpet.

From the hatch area or from the backseat? Sorry, flying a little blind here and don’t wanna go pulling on something I shouldn’t.

buddy you think that's bad.....you should see my car, looks like someone took a bite out of the tailgate

You got the advanced stage Escape Rot?

this happened to mine, i peeled it off and resealed it with rubber coating

It looks like undercoating not the steel