(I wasn't able to read the full article but I get the gist from what the posters have stated.)
If everything goes perfectly smoothly in his life, then yes, there was no harm to himself or others in the way he's living his life. The problem though is living so extravagantly makes him so much more vulnerable to all these curveballs life throws at people. He could lose his job, get in a serious accident, have a cancer scare, fall victim to a crime, injure a pedestrian, lose all his worldly goods in a fire, etc. Will all those happen to him? No. Will something happen to him in the course of his life? There's a pretty good chance it will. Without a buffer in lifestyle, adequate protection, nest eggs, etc. he's so much more at risk that a single event will just obliterate him.
I've seen these statistics claiming major sources of debt for most people come less from conspicuous consumption and more from traumatic events that have inherently large bills (medical debt) or require debt to survive (buying food after a job loss). But all these studies fail to acknowledge that the "reasonable" lifestyle before hand is what lead to these people not have a cushion in the first place. The pros on this forum could have any of these bad things happen to them too, but their reserves and resourcefulness would allow them to take it in stride and bounce back unscathed.
There are so many people who legitimately cannot prepare and protect themselves adequately. These people have no choice but to hope their luck holds out long enough for them to get a leg up and I'm glad there are public assistance methods to help them when the shit hits the fan.
The author is truly failing to recognize what amazing privilege and opportunity he has right now to help his future self get through a hard time. He instead chooses to squander it and that is very sad.