This is a question that keeps popping up, and it's probably because many people don't wear suspenders or know anyone who wears them, at least not on a daily basis. But the fact is that many people wear suspenders for one occasion or another.
Some people only wear suspenders for formal occasions. For instance, they may be required to wear them as part of a wedding party, or they may decide to wear them to prom. There's another group of people who like wearing novelty suspenders for Halloween or other holidays. And then there are the dedicated suspender fans who wear them to work, school or just about any time. In short, yes, suspenders are still in fashion - they're just worn in different ways by different people.