For certain types of riding, sure Lycra makes sense. But I also view it as a barrier to riding. When I was a kid, I never put on special clothes to ride my bike. And now that I spend most of my days chasing an almost-toddler, I don't really have time to change into a separate outfit to ride to the store. I purposely chose my latest bike to be something that I would be comfortable wearing street clothes on. Right now I'm doing mostly city riding, either to go to the store or some other errand, and I'm not doing very long rides. So there's no point in changing clothes. I sit more upright, so I don't need a ton of stretch in the seat, and the bike has a chain guard so I don't have to worry about getting grease on my pants. Pedals are flat so I can wear regular street shoes. This suits me just fine at this stage in my life.
Someday I'll go back to riding dozens of miles a day, and the Lycra will come out again.
2014 Bobbin Bramble / Brooks B67
2008 Rodriguez Rainier Mirage / Terry Butterfly Tri Gel
2007 Dahon Speed Pro TT / Biologic Velvet