But some UFO experts say the former insiders' accounts don't necessarily eliminate the possibility that Area 51 is indeed home to some UFO-related activities.
"Those guys who came forward may very well be telling the truth, with the caveat that they wouldn't know if there was something going on," said Stanton T. Friedman, a nuclear physicist, lecturer and top UFO researcher.
Highly classified work is also highly compartmentalized, he said. And the absence of evidence on their part isn't the same thing as the absence of evidence for such work, he suggested.
Friedman said it's still conceivable that wreckage from what some people believe was a UFO crash in Roswell, N.M., could have been transported to Area 51. And, he added, "of course" the military has an underground base out there.
But, regardless of whether or not Area 51 is indeed connected to UFO activities, Friedman pointed out that the facility has captured the imagination of Americans for another important reason.
It has become a symbol of government secrets and the universe of information too sensitive for public consumption.
As a scientist for General Electric, Westinghouse, McDonnell Douglas and other high-tech companies, Friedman said he's worked on a variety of classified projects that have shown him government secrets are a fact of life.
Area 51 is just one example of that.
"National security has a real place in all of this stuff. There is no way to tell your friends without telling your enemies," he said. "A lot of Americans woke up to the fact that there's a lot going on that they don't get told about."
ABC News' Lee Speigel contributed to this report.