Simply stated, the author is criticizing contemporary journalists as being less competent than those of the past.
In other words, he believes that basic skills of journalism (although this includes being a critic, as well) are substandard or lacking altogether.
It's true that the notion of journalistic "calling" was mentioned in the article but that's not what the article is about. I'd also point out that 'calling' does not mean 'duty.' Duty is a legal and certainly a moral obligation, not a calling. Keep in mind that of course one has duties both legal and moral within one's calling. In other words,
if one is called to be a surgeon, for instance, a surgeon has the legal and moral duties to uphold laws governing the practice of medicine and moral obligations to provide the best service to her patients.