Three weeks ago, a spring breaker in Miami became a symbol of Gen Z denialism when he spoke to CBS News and said that coronavirus wasn’t going to get in the way of his partying.

Outrage was swift, but one person who felt a touch of recognition was Peter Staley, one of the country’s most respected AIDS activists.

Mr. Staley, 59, remembers what it was to be young and dumb.

In the summer of 1983, shortly after graduating from college, Mr. Staley moved to New York City and began inching his way out of the closet. In the East Village, hanging out at places like Boy Bar, he heard in “this abstract rumor-mill way” of a plague that was killing gay men.

“My first instinct was like that kid on the beach,” Mr. Staley said. “There was this whole thing of, ‘I’m hearing it’s only happening to the older gays and the ones who slept with hundreds of guys.’ It was so easy to shrug off.”