I see this constantly on social media, including MN. Whenever a discussion starts about cyclists people start using phrases like "lycra wearing" as an insult.
I cycle for pleasure and commuting, not for speed, and I wear lycra/cycling clothing because it's the most sensible option. Padded shorts or leggings because 30 miles on a bike is painful without them. A cycling top because of the pockets in the back for phone, keys, wallet etc. Plus the tops are breathable. I'm an overweight woman in my 50s so I'm not doing it for fashion purposes but because it's the most practical option.
However wearing lycra seems to be a complete no-no according to non cyclists. I was on a FB page yesterday where a horse rider was (quite rightly) complaining about cyclists not knowing how to approach horses on the road. She then made a disparaging remark about "the lycra-wearing brigade". No one criticises horse riders for wearing jodhpurs and riding boots.
Surely with most sports or exercise you wear what is most suitable? So if you go swimming you wear a swimming costume, if you play football you wear kit, so why the dislike of cyclists wearing cycle clothing?