I haven't seen the substack post nor podcast episode, but I have read the book.
I have to say that while there was plenty in the book that I couldn't relate to (going into debt while young to take a traveling gap year, or taking family on ostentatious party vacations), there were other aspects that I did find meaningful.
Chief among those from the quote you raised: "…you’ve essentially wasted precious life energy working for dollars you never got to enjoy"
I was planning on waiting a few more years for the Rule of 55 before I'd leave the workplace. I hadn't honestly evaluated whether I was at my FIRE number or not already. But this book got me thinking about the limited time we have on this earth, and that you can never buy back a single day of life once your time is up. Time is a precious commodity.
After reading "Die with Zero" and "Outlive", I evaluated my position and decided to pull the trigger, spend time on things that are meaningful to me, and to work on my neglected fitness so I might be able to stick around and enjoy a longer life and health span than I otherwise would working my long hours, high stress corporate job.
It's given me more time with family, opportunities to volunteer, much more sleep than I'd been getting before, and I've walked a lot of miles, listened to a lot of audiobooks, ushered at theater, and started a weight training program. I'm relaxed and happy, and I'm enjoying participating more within my community.
If I hadn't read those two books, I think I'd still be on the corporate treadmill for a few more years.