If long or longer hair works for men over 60, all the power to them.
Prerequisites (in my books) as to a man, any man, sporting long or longer hair... hair must be thick and full (not stringy), and have a nice style about it, and IMO nothing beats a man with naturally wavy hair. My husband has the most gorgeous of locks... dark, thick, wavy, OMG, still drives me wild after all these years.
Dear husband is nearing 60, and still looks like he's in his late 40's, courtesy of his dark, youthful, thick wavy mane.