Well, for whatever reason a bevy of riders crash that corner seemingly every day. Usually it's just past where this guy crashed (at the exit).
looks like this guy had a bad line, bad form and was forced to make a lean angle/trajectory adjustment that led to the low side (thanks to the aforementioned two "bads.")

seen so many vids of that corner eating bikes I'm starting to believe there is something on the pavement there
I'm guessing excessive lean angle for given speed

Well, for whatever reason a bevy of riders crash that corner seemingly every day. Usually it's just past where this guy crashed (at the exit).
seen so many vids of that corner eating bikes
Aside from the rider and the state of the tires or equipment, have a look at the turn at 1:52 and see what I see.