That Wikipedia page says viewings are basically the same as a wake. Are viewings not common in the U.S? They're common in Utah.
When my dad died, before the viewing there was the period right after death where my siblings and I sat in the room with his body and talked until the mortuary picked him up.
My suspicion is that the proliferation of cremation has significantly reduced the incidence of wakes. That, and US American society has so much functional separation that most of us probably interact very little with the elderly, thus also not ending up at many funerals.
We have wakes and visitations in Canada too, but they are held at funeral homes for brief periods - not in the home of the deceased or a loved one. I think this might be the same as the Jewish ritual of “sitting shiva”?? But I am not sure.
When my dad died, before the viewing there was the period right after death where my siblings and I sat in the room with his body and talked until the mortuary picked him up.