Not so. If the primary cause is, say, a control cable to the tailplane snapping (or a critical instrument failure in IMC), that is not listed as pilot error, but a systems problem. In the Airbus case, the ‘control cable’ is an FCS computer and an electrical wire.
No modern fly-by-wire design has a single point failure mechanism in any aspect of flight control systems.
The FCS controllers are typically triple redundant and the control system actuators also have redundancy.
In addition reliability testing is done to the nth degree on all electro-mechanical systems that actuate flight control surfaces.
Aircraft break-up, serious design flaws, serious software errors or pilot error are realistically the only things that could compromise the systems.
Entering weather, even thunderstorms would likely not be the cause of the crash, just a contributing factor. If the pilot lost his plane solely due to the thunderstorm, then, again it is pilot error because he made a bad decision to penetrate the storm.
My bet on the outcome of this investigation? The finding will be pilot error.