He claim the water cell is a generator of electricity and that this is the only key to economically split the water
Ask yourself how can you have electrical power generation in a resonant system with no moving parts?
When a covalent bond is broken, electrons are released.
Those electrons that were in the orbits of Oxygen and Hydrogen.
Not those electrons that came from the electrical circuit and from the metal.
Namely, electrons from broken water molecules.
The electrons from the circuit cannot get into the water.
As a result, there is no electrolysis.
The electrons from the water create an electric current.
The number of electrons will be approximately equal to the number of broken water molecules.
The high potential difference causes them to leave the Meyer cell and enter the generator circuit.
In simple terms, free electrons from metal are replaced by freed electrons from water.