I don’t speculate and will leave this to the rudder people. I only deal with facts... The initial BEA report does not support your conclusion...
The Wright Brothers invention that permitted controlled flight was the rudder.
Without it, even gliders would go into a descending spiral and then into a spin.
An airplane will always go into a spin if it loses the vertical tail. The vertical tail was miles away from the rest of the wreckage.
Boeing tails do not break off because they have metal attachments. Carbon fiber attachments shatter when they are over stressed. Metal attachments may deform, but they do not shatter.
The "official" investigation is political.