I'm sure 90% of ordinary riders would brake all the way down that hill. But my comments pertained to the other 10%, a TDF peloton.
The guy with the cam is certainly a great downhill rider, but you can see him having to using the brakes at times on the worst hairpins, often because slower less brave riders get in his way. He's a brave rider, often forced to take the bad line through the corners by the others, but still barely using his brakes at all.
But sure, of course even in the TDF, riders brake on the worst corners. Not braking soon enough is how guys end up laying it down, riding off between the caravans, etc. Some of the best riders have had it happen, as they scream into those corners eyeballing each other to see who will chicken and hit the brakes first. They know every touch of the brakes costs them watts if they have to catch back up with a peloton at the bottom of the next pass.
Back to the subject of light, back when we used to gravity race the Emory Pass, I weighed 115. So bike and rider were under 150 pounds and got great grip on those skinny tires. Not that weight now of course. We all know what another 60 pounds added to a bike at saddle height does to the handling. Road surface matters too. A few years back I revisited Emory Pass, and was astonished how slow the descent was. I was on fat tires, but the real difference was that the road had been chip sealed about a month before. The sharp rough gravel made it ride like a brake on, or a dd hubmotor was slowing you. Back again a year later, the road was back to it's normal zippy character once the gravel packed into the tar. Ten full miles of 8-10% grade so it's very fast again. Now 40 years later, I brake nearly all the corners going down it.
The hairpins cars take at 15 mph I now take at only about 30 mph. Used to do them at 50. Still catch a few motorcycles going down, but not the racing kind.