Maintenance is indeed important for longevity and avoiding usually unnecessary repairs. A long time customer had a transmission go bad. He wanted to know why and I asked if he had ever serviced the transmission because the fluid was nasty. He stated that his father told him servicing a trans was the quickest way to have them go bad.
My question back was if this was so, why is there a serviceable filter? Would the filter never clog or become restricted?
Myth: Serving transmission is bad.
Truth: Changing the fluid and or filter helps keep fluid flow and quality of fluid good, hence longevity for the unit.
Could the repair of this transmission been avoided? Yes and no. In this case yes, but even with proper maintenance sooner or later all transmissions wear out, so later in this case would have been preferred.