Can people be bred for tameness in a similar way to Russian foxes?

Setting aside the eugenic implications of what are you suggesting (short answer: yes it is theoretically possible, but no it is practically impossible), a more interesting observation is that evolutionary anthropologists think that humans might have "self-domesticated" during our evolutionary history.

There is a wide literature on this topic, but a recent paper summarizes the main ideas and addresses the question from a genomic point of view. Theofanopoulou and coauthors find credible genomic evidence for similar patterns of genetic evolution in humans and other domesticated animals.