Perhaps 40+years ago (I'm 57) I remember watching a show on television, which may have been an old movie or even an early television show like The Outer Limits.

The setting was very 1930's / art deco.

The story began with two "upper class" women talking breezily about the decline in human population, and whether they should have a robot (android) lover.

There were scenes showing the robot temple, the only place biological humans agreed not to enter.

There was a man in the story, very skeptical about the whole state of affairs.

At some point the man is approached by two robots, and they discuss the fact that humanity is doomed to extinction by the decline in fertility (was it disease? War? The consequences of technology?).

Finally, they reveal to the male protagonist that he himself is a robot, much to his surprise. They remind him of a night when he was walking alone... and was killed.

The robots are revealed to be not threatening, but the saviors of mankind's souls and legacy. By perfecting the capture of a person's essence they will help humanity survive its own extinction.