I would have found it much more interesting and useful if the author had tried to sincerely answer or even ask the question of the title. Instead it’s just a complaint.
At the end of the post, "The larger employers and job-hosting web sites need to get their acts together and work this out".
In a comment right below, the author says that this would be "giving job-seekers more control over their data".
Obviously, the larger employees and job-hosting web sites have no interest in allowing job-seekers more control over their data, quite the opposite, so they won't. And their active cooperation is absolutely required for such a data format to be adopted - so it won't be, at least not in a way that satisfies the author's wish of gaining more control over their data. That's it, it's that simple.