As long as you know how to edit metadata, you can definitely fool minor “trust systems” like adjusters, police, etc. It’s a big gap. (For any future readers, no I have not done this and would never do it, really.)

The only solution I see is some kind of hardware-linked signature showing that the image was produced at a certain time, by a certain device. In theory, you could make this signature somewhat “provable” and anchored to a specific time by combining something like 1) the latest Bitcoin block hash, and 2) a blockchain anchor, thereby proving that the photo was taken within a certain time widow after the hash was known and before the anchor was published. But even that arrangement is highly susceptible to hardware attacks.