It’s because he only knows how to destroy, not build, and destroying is always easier than building. It may be impactful but it is going to set America back decades.
He's destroying for various reasons yes. But he knows how to build. Perhaps not personally, but he can wrangle a system to do things for him, mostly for him perhaps. OK completely for himself, but that's not to say he can't.
The only thing he has ever directed that has been a net positive to society, Operation Warp Speed, is something he disowns because of the rabid anti-science stance of his base.
While a politician. You do realize he built many things or headed the building of many things prior to being a politician? In some cases to net good for the world, unbelievably. It's easy to vilify him for political or personal choices but that's not to say he can't do things.