You might, of course, suppose the phenomenon to be New York specific, or limited to the coasts. But a survey of the landscape suggests we may have entered an age of sartorial advancement. At the very least, there has been a course correction. A generation raised on the insult-to-the-eyes that was casual Fridays has suddenly discovered a novel new uniform: the suit. The last person anyone wants to dress like these days is Tim Allen.

Thus the frumpy Dockers and the men’s version of mom jeans and the oversize shirts billowing like jibs have been bagged up and shipped to Goodwill. Even dot-com geeks have slowly begun moving away from the hoodies and sneakers, knit-hat-and-sweatshirt Smurf look. In Silcon Valley these days, the stealth signifier of status is that throwback to the glory days of haberdashery: brightly patterned socks.

I asked the experts at the recent men’s-wear shows in Milan how had the change come about. How do you account for the apparent spike in the fashion I.Q. of the average American male? Is it fallout from years of so-called reality TV shows, the ones where anointed gay tastemakers descend on some slob in his mother’s basement and sprinkle him with pixie dust?

It can’t be that, really. For one, the gay stereotypes don’t hold up. The guys from the corner of Queer and Gay Streets tended to dress like jokers in square-toed shoes and whiskered jeans and the silly muscle shirts one associates with certain preening news anchors.

“Now, everyone knows everything,” Wendell Brown, a senior fashion editor at Esquire, told me recently. Growing up in the 1980s, Brown felt forced to hide his issues of GQ under the bed to avoid detection, not quite ready to come out to his parents as a Perry Ellis fan. “We are so far beyond that whole metrosexual phase, that ‘Is he gay?’ stigma.”

Brown knew it had all changed, he said, when a female colleague in his office, an untrendy type whose boyfriend was a former frat boy, asked him if he could hook her fellow up with a suit from Thom Browne.

There was a time when the notion of a good old boy coveting one of Browne’s shrunken suits — the ones with the high-water pants and jackets barely skimming one’s bottom — would have been more than implausible, a “Zoolander” fantasy. Yet barely a decade ago, when Browne was still catering to a select handful of clients and had no wholesale business, his customer base was already skewing toward in-the-know Wall Street types, said Tom Kalenderian, the executive vice president of Barneys New York.