I think the word feudalism needs to be connected specifically to the system of land rights that it enforced, otherwise the word loses most of its meaning.

Because if "feudalism" simply refers to power and loyalty relationships, then it simply describes dynamics that exist under any organized system with humans in it, and thus it can be used to describe anything. "Technofeudalism" "Corpofeudalism" "Medicalfeudalism", etc... it would all apply.