Somewhat agree. If you really want to understand lean principles, start with the masters of the topic and consider reading some books about Toyota. The first in the list below is a wonderful introduction to how lean manufacturing principles evolved at Toyota over decades. The others can provide more hands on experience on the topic and if you can mentally translate manufacturing principles to software construction techniques, everything will start to make sense.
I'm glad someone points to this. Quite often, criticism of "lean" is about stating that with a MVP you cannot make a car (with illustrations of skateboards and bicycles…)
But really, I can't see a better example for Lean than what car makers do.
The Machine that Changed the World
https://www.amazon.com/Machine-That-Changed-World-Revolution...
Toyota Production System Beyond Large Scale
https://www.amazon.com/Toyota-Production-System-Beyond-Large...
The Toyota Way
https://www.amazon.com/Toyota-Way-Management-Principles-Manu...
Out of the Crisis
https://www.amazon.com/Out-Crisis-W-Edwards-Deming/dp/091137...