Neofeudalism is only possible in an agrarian society, or if your income is digging stuff out of the ground.

Industrialized societies quickly tear themselves apart when you need an educated workforce, and intelligent consumers.

A society of serfs will only consume the bare minimum, stagnating technological progress, ask the chinese about gunpowder and naval force projection.

Unlikely for the US to enter Neofeudalism when we are entering an age of great power competition.

You only get to keep your power if you "bribe" your workers enough to help you.