Yeah, the assumptions for this counter-argument to FIRE are pretty hodge-podge.
It wasn't even a well-researched hodge-podge. These sorts of opinion pages usually shout about the rising costs of healthcare and college and the current CAPE ratio as part of their assault on the idea of financial freedom.
But in all honesty those are just distractions. The underlying sentiment behind this piece and all of the others like it is basically America's Puritan work ethic, that it is somehow more moral to work than to be free of the necessity to work (whether you choose to work or not), which just means that it is perceived to be moral to be bound in servitude. Which isn't really a surprise, the Church has been teaching this lesson for thousands of years now.
Entrenched power has ALWAYS taught that it is noble to toil, to labor in service to the Pharaoh/Sultan/King, because those people in power have always depended on the work of others to support their life of idle luxury. They have justified it at one time or another as a noble obligation, or the duty of royalty to "serve" the people by leading them, but in truth it is hard to serve while being fed grapes by your harem or rolling around in your treasure vault like Scrooge McDuck.
We live in interesting times. Technology and information sharing has suddenly made it possible for the average feudal peasant to work towards a life comparable to that of the King. The stock market is essentially a mechanism for sharing the profits of our workforce with a slightly larger number of people, and that allows a reasonably talented and industrious laborer to buy himself free of the obligations to toil in service to another.
Of course the people who have always been free of this obligations are worried about it, because they feel it threatens their own security, and so they work to perpetuate this myth of noble service:
"Oh no, you don't want to be free, work gives your life meaning and purpose!" (Never mind that I don't work.)
"Remember serfs, the best life is the most destructively consumptive one you can possible afford!" (Never mind that I carefully marshal my assets to avoid depleting them.)
"Financial independence is all built on a mathematical fallacy! It will never work!" (Never mind that it has always worked out great for the world's most successful and important people.)
Such an obvious crock of hypocritical bullshit. And the worst part, to me, is that these deliberately misleading attempts to control you are now being parroted by well-meaning peasants and serfs, instead of just by the financially independent wealthy royalty.