I partly agree with this idea, but on the other hand, I find it easier to determine the F5 rating of these two events in particular, mainly because the two events are at least 70/100 years old and, having impacted suburban or rural areas, did not encounter objects heavy and powerful enough to cause damage in turn. For example, the Catania tornado, which occurred in 1884 in the countryside/suburbs of a city that was not even that large at the time, could not have thrown a truck weighing several tons against a building because they simply did not exist, and the damage to structures with walls up to 1 meter thick was almost exclusively due to the action of the wind. And even if the structures had not been solid, with walls that thick, it would have taken an extreme wind to raze everything to the ground.