Aside from the emergency shut off not being in the same room would this ok to have the wires going through the garage ceiling?
Is that a wet location flexible conduit like LFMC? If so it is permitted to be run to the water heater but it requires proper support and securing. Where flexibility is require after installation you would be allowed up to 3’ from the last support to the appliance. {350.30(A)Exception(2)(1)}
One could argue that a HWH does not meet the flexibility requirement therefore the last support needs to be within 12" of the termination on the HWH.