Earlier quoted context omitted.
Well you normally don't kill someone else if you fall off a roof. Running a car at highway speeds into something or someone else has a much higher chance of injuring or killing multiple people besides the driver.
“Older drivers have 3 to 20 times higher risk of fatal crash than non-older drivers” [1]. We simply don’t have those data for roofers. [1] https://www.sciencedirect.com/science/article/abs/pii/S01674...
Like motorcycles are orders of magnitude higher risk for (including fatal) accidents - but they aren't as dangerous for other traffic participants so they get licensed.
If motorcycles were killing orders of magnitude more pedestrians or other traffic participants than cars they would get banned immediately.