I share your feelings, but I think we need to be realistic about it. Unfortunately, these days if there is no financial benefit to the salvage firms, they won't commit the resources. Mostly, some sort of compromise has to be negotiated. You can say, "Well, then just leave it alone, in that case," but all over the world, shipwrecks are disintegrating at an alarming rate. Some due to natural forces, but many others due to drag nets and looting. Undersea archaeological remains are suffering from looters, just as sites on dry land are, and it's a grim race to see whether museums or private collectors get the artifacts first.
If there is not an International effort to systematically protect, excavate and salvage shipwrecks, they are all going to disappear, one way or another, and we will be left without any of the historical benefits that all of us should be able to enjoy. What good does it do to have a wreck like Graf Spee slowly sink into the mud, or be looted by unofficial and unmonitored treasure seekers? The problem is that there is not enough money available in the world to salvage these wrecks properly, and the only way I can see to save anything for the sake of history is for museums and nations to work with commercial enterprises to beet the looters to the punch. And that means compromising so that the commercial enterprises gain something from their efforts. Sad to say that things have degenerated to this point, but that's just the way it is.