Absolutely terrible.
Though, what damage other than crashed debris in a remote land, is exactly done?
Not to support the act anyway, but as long as no one got hurt, one may not face 20 years jail time for crashing their own plane in a remote land.
Stupid? Absolutely.
Illegal? Shouldn't be.
He's facing 20 years of jail time for wanton destruction of evidence and impeding a federal investigation. The FAA doesn't have the resources to launch a deep detective dive on every crash, and the penalties are set to highly discourage the practice of impeding understanding of what happened in a crash because that's part of the process of making the air safer for everyone (ground-side as well as air-side).
Even the wreck itself, in its undisturbed state, would have been valuable for better understanding of how an uncontrolled plane meets its end (including possible opportunities to improve the safety of the inevitable disassembly when it finds the ground). ... unless some likes-hound cuts the plane up into tiny pieces and tries to hide it.