I would have differed in opinion a few years ago, but with some experience in both international financial platforms and as a product manager with a company that have made the mistake of not investing in long-term technical hires with the talent and skills needed (which means compensating them properly and not relying on the goodness of their heart), I agree with this article. If a team continues to be hacked together, the code will continue to be hacked together. It may be cleaned up in the short term, but the cycle of technical debt and building inefficient code will eventually continue.
I agree that getting yourself out of a coding mess brought on by low paid contractors via a volunteer contractor instead doesn't make a whole lot of sense.