As others have already posted, the website cited has been around for many years and is often referenced.
Although the doctor that created the website seems to make some very legitimate points, it's funny that the majority of his classmates and DPM's before and after him seemed to find a way to make it work.
There are always obstacles that can appear to hinder your path. Some of those can be financial, some of those can be political, some of those can be academic, some of those can be self induced, some of those can be due to geographic areas, some of those can be due to poor decisions, some of those can be due to bad luck, some of those can be due to health, some of those can be due to family, friends or colleagues and some of those can be due to poor business.
It's always easy to find an excuse or point a finger at someone, but it's much more difficult to battle your way out of the situation and succeed.
However, I can guarantee you that when you succeed, you will appreciate it much more and you will never look back.
There will always be those that were unhappy with their career choices, and I truly feel sorry for the doctor that created that website, and hope that someday he finds his "nirvana".