Ryan was reacting to Hollaback! The Irish branch of the US website encourages women to share their experiences of male attention by posting photos and videos of 'male street harassment'.
The site plans to 'out' men who subject women to unwelcome remarks, wolf-whistles or sexual insults.
"I find political correctness tedious," the 39-year-old said. "I think political correctness is one of the things that has killed passion, it has killed debate, it's killed fun."
While Ryan defended wolf-whistlers, he insists it's not how he catches the ladies' eyes.
"I wouldn't be inclined to wolf-whistle myself at all," he added. "But I think having a ban on it is completely ridiculous."
At the launch of Denim Day 2012, he also hit back at comments by radio rival Ray D'Arcy.
D'Arcy had claimed that Tubridy needed to take fewer holidays if he wanted to keep his ratings up.
"I don't think I take too many holidays," he said. "My time spent at the BBC wasn't holidays; it was work. I'm working the whole time."
But Ryan is looking forward to spending this Christmas finishing his latest book.
"It's about Ireland and Britain and popular culture. It's going to feature Irish men and women who made it big in the UK. Broadcasters, entrepreneurs -- that sort of thing.
"Britain needs to remember how brilliant Ireland has been to it."