However the example of a contractor who lives an unencumbered life and saves a lot of money is not at all typical. It's similar to using the example of an investment banking associate or corporate attorney who pay high rent in Manhattan for some years and invest the rest, as an argument against buying a home and having a mortgage.
In reality, many/most people are better off with a mortgage because it forces them to save money, which they behaviorally wouldn't be able to do otherwise. Likewise, buying something and keeping it around probably prevents a lot of needless repurchases and upgrades of the same item. If you are rational the rental lifestyle can make sense in some cases. But for most it just facilitates impulsive behavior. Hence the rush to capitalize on it.
I'm going to go ahead and guess you don't have a large peer group who were buying houses in the late-2000s. A mortgage in no way forces you to save money, added to which it has a tendency to decrease savings due to the moral licensing of exactly your train of thought. "I'm already saving with my sweet ARM, I can afford to lease that car!"
People who are financially illiterate are going to be bad with money, regardless of the system.
I am curious though as to the distribution of freelance / contract rates. Is $200 / hour also 1% of engineers? More? Less? Financially for the same person what's actually a better route? For someone that can get $400k a year at google, is that better or worse than the contract route on average?
Not owning anything allows you to go where the work is and keep your net worth in assets that produce actual income (like index funds and bonds), instead of sitting around collecting unemployment during a dry spell because you're encumbered by your depreciating assets.
I'm sure some people will use this as a way to temporarily live beyond their means...but it's not like Credit Cards don't enable this behavior already. The US is the land of the free of course, where we allow the weak to be preyed upon.