@horseless carriage With that lovely posture, you'd look great in anything. I'm so jealous!
What a lovely compliment, thank you.
A couple of years before the Covid lockdown, I went into hospital for a hip replacement. The surgeon who performed the operation told me that it all went well and that, if I take care of it, my new hip will see me out. Apparently artificial joints have a shelf life. My surgeon went on to say that exercise was good but to avoid impact exercise, meaning jogging. Swimming is great, but cycling is best because of the nature of pedalling, it rotates the hip joint.
In the UK these days there's been a resurgence of cycling, they seem to be everywhere, you can't miss them, in fact one national newspaper dubbed them "lycra louts." The play on words comes from what we call boorish drunks, that being "lager louts."

Now I don't know about you, but when I cycled to school the word lycra was unheard of, probably some foreign word.
Can you imagine me in stretchy lycra? So when it was suggested that cycling was a great way to exercise the new hip joint,
what do you think that I wore? And what do you think my mode of bicycle was?

My bicycle is a 1928 Philips, it's a lady's bike, having no crossbar, perfect for a healing hip joint. The trousers that I'm wearing, that my wife made for me, are secured with bicycle clips.
As the O/P said, have we gone too casual? Well you can keep your lycra-lout look, a sports blazer is casual enough for me, thank you.