I don't believe these kind of projects are designed to be economical :). He is building this to drive traffic to his youtube channel, which in turns, pays for the next outlandish project.
They can be made economical if you have a lot of salvaged parts for cheap / free.
(As a boy, I could not have built much of the stuff I've built from 74xx ICs if I had to buy all of them new; instead, I had a bunch of PCBs from a decommissioned computer.)
(As a boy, I could not have built much of the stuff I've built from 74xx ICs if I had to buy all of them new; instead, I had a bunch of PCBs from a decommissioned computer.)