I have found there are a couple specific situations where I like specific footwear. I hardly fit in the back seat of a cub, and when I have a large student in front, my feet are impeded, stuck between the wall and the seat. So I got some little leather booties to wear so the shoe has no structure, and that makes it so my feet can move if needed and also can stay out of the way.
As an instructor in a 185, I have found that a boot with a bulky, stiff toe is a problem because if you apply left brake, there is a little fitting right in front of the pedal that my toe can get stuck under. So if I am instructing in a 185, I wear boots that don't have much structure, and then it is fine.
In general, I fly with some sort of boot appropriate to walking and surviving the terrain of the flight. Mostly I fly cub, 185, beaver, and my own little tripacer. Winter boots, general purpose leather boots, all of them work fine, but you might need to spend a minute and think through the way you and your feet fit to make sure you don't have any surprises. But I would avoid putting yourself into a decision matrix where the only footwear you fly in are not adequate to the task. I have made a couple accommodations where it was needed but I don't generally fly with anything less than a good leather boot.
