If you don't wear a pointy hat etc
Hi J.A.F.O.
Being serious about it, I reckon each pilot has to make a value judgement based on a balance of comfort, practicality, risk and cost.
If all the flying you do is 12 hours a year in a Pa28, then you may as well stick to your third best street clothing.
If you fly professionally, the company will insist you wear a natty looking (but cheap) uniform. (One thing that concerns me is the silly uniforms instructors are so often required to wear these days, bearing in mind the inherently hazardous work they do. These uniforms are made of synthetic fabrics that, in the event of fire, will melt onto the skin and burn like a torch. Personally, I would give all instructors Nomex gear).
At the other end of the scale, if you are a military pilot or fly hundreds of hours annually, perhaps crop dusting or doing some other hazardous occupation, then you really need the whole works, bone dome with oxygen mask, leather boots, Nomex grow-bag, scarf, wrist covering and socks, and Nomex or leather gloves.
In terms of practicality, wherever there are aeroplanes there is oil, petrol, hydraulic fluid, sharp protrusions and mud. So you don't want to be wearing your Sunday best. You also need to take into account the weather and temperatures you will be working in.
So overall, each of us needs to know what is available to choose from and then choose with common sense.
Broomstick.