I didn’t say the H.S. does “inhabit” a dead body. But one of the effects of Baptism is the indwelling of the H.S. Indeed, the Trinity. Thus, the body of a baptized person, even after death, deserves a great deal more respect than an old coat or other object.
You wrote that the Trinity inhabits the body even after death. I basically asked what’s the point. The soul and spirit of the person is gone. Then too, why give all this respect to a dead person when in many cases they never got that respect in life?