Yes, testosterone deficiency is, for the most part, made up marketing bull.

The Atlantic article is long so I'll just highlight the most important part:

According to British Medical Journal (BMJ), the European Male Ageing Study has provided the best estimate of the prevalence of low T -- defined as a combination of sexual symptoms and measured testosterone level -- finding that only 0.1 percent of men in their forties, 0.6 percent in their fifties, 3.2 percent in their sixties, and 5.1 percent of men in their seventies would meet the criteria for the diagnosis.

Unlike menopause in women -- when estrogen levels plummet and stop almost completely -- testosterone levels in men normally fall by only 1 to 2 percent per year after age 40. 

"Low T" is anything but inevitable. BMJ's Drug and Therapeutics Bulletin says that around 80 percent of 60-year-old men, and half of those in their eighties, have testosterone levels within the normal range for younger men. It concluded, "The evidence that an age-related reduction in testosterone levels causes specific symptoms is weak." The Food and Drug Administration (FDA) meanwhile has not approved testosterone use to improve strength, athletic performance, physical appearance, or prevent aging. And a 2004 report from the Institute of Medicine ("Testosterone and Aging: Clinical Research Directions") called TRT for age-related testosterone decline a "scientifically unproven method."

"A proportion of older men will predictably have testosterone concentrations below the normal range of healthy young men," wrote BMJ deputy editor Tony Delamothe, in a 2012 commentary. He added, "It seems a bit harsh to turn an age-related phenomenon into a disease, but that's what's happened."

In the age-old tradition of snake oil peddlers and traveling medicine shows, Testosterone Replacement Therapy is but the latest elixir from the fountain of youth. Offering a heady brew of hope and hype distilled at the drawing boards of advertising agencies, tubes of testosterone are the latest wares for the unwary.

I think you should qualify that... .as "age related" testosterone deficiency is marketing bull... lots of legit need

Good point, fixed. Thanks Jason!