I don't commute in Lycra, but I don't commute in my work clothes, either.
My standard "kit" for cycling is gym shorts and inexpensive "dri-fit" type t shirts. In the rain, I use cycling specific rain pants and a cycling specific rain jacket because I live in Portland OR and cycling specific rain gear just works better. Some of my gloves are cycling specific, and some are not.
I do run clipless pedals and drop bars, but I don't own a road bike. I commute on a touring bike with racks and panniers or a cyclocross bike with racks when I'm feeling sporty. My commute is about 10km one way, so relatively short.
i have showers at my office and plenty of space to store clothes, shoes, towel, and Dopp kit.
Whatever works for someone is fine with me.