I think you never want to freewheel corners in any vehicle. You want the motor connected to the driving wheels as much as possible. Sure, if I am coming to a stop I will simply pull in the clutch and downshift all the way while using the brakes to stop. But never on a track; and almost never if I am not coming to a stop.
Matching gears: Downshifting is a big part of my fun when riding in a spirited fashion. I like to use mostly the front brake when on the tar. I like heavyish front wheel braking with a constant pressure on the lever, while blipping the throttle with the same hand. While I am not a road racer, both of my sons are and I learned that little technique from them. And BTW, they had slippers and speedshifters to help. But the downshifting is a bit of an art that is special for me.
I am pretty abrupt with the clutch, though. I have a bad habit of popping it out. Like bang! A bad habit.