I've been working as a freelancer for a bit more than a year now and let me offer a counter perspective.
This article is a report from the absolute bottom. Part of the problem is the clientele: data scraping jobs are the shadiest, worst-paid jobs you can take on as a programmer. Also, offering the client to pay what they think is fair is a monumentally bad idea.
The bigger problem is the perception of value. I regularly get requests for doing insane amounts of work (usually it involves cloning a multi-million dollar site or app) for less than I charge for a single day. There are "idea people" out there, who think the goal to success is paying someone 300 bucks to implement a clone of the Android app store. It's a real example by the way. I mainly get my work through the Who Is Hiring thread on HN, and although the overall client quality has been high, it's unavoidable that over half of all requests are absolute bogus.
I suspect I'm not the only one having this experience. Now, these inquiries can be effortlessly ignored (I usually do answer them back with or without a short statement why I'm not taking the job) - however, if you're just scraping by, these "gigs" can totally demoralize you.
To an average person, programming is not a valuable thing, and they do not view it as skilled labour. This has been the case for as long as I can remember. After high school, twenty years ago, a friend and I got into freelancing. A lot of inquiries were pretty much the same as they are now. My friend used to say we should rebrand ourselves as the Web Sherpas, named after the local people who often get hired for grating or dangerous work on behalf of tourists yet receive little compensation for it.
To the freelancer just starting out I say: don't get suckered into these kinds of debates, be friendly but firm in rejecting malicious "job offers". Holding out until the right client comes along can be tough, and you're going to need a financial buffer to do this. But it's definitely the only way to go. People taking $15/hour data scraping jobs are part of the problem because they help distort the value perception of our profession (plus they help making the internet a worse place). Don't be that person.