It isn't that difficult to reach down and unsnap it. In most cases you are better off staying with the tractor, but somebody always comes up with that one exception and treats it as gospel..Assuming it's not AI....
This video raises an interesting question. We are told to always wear the seatbelt if the tractor has a ROPS. Assuming it had a ROPS and not just a canopy, do we think he would have been better off belted in as per the common advice or being able to bail like he did?