Your son must have taken after his mom

Honestly some electric cars have transmission fluid, while others do not.
Their electric driving motors can apply torque in a much more consistent and fine-tuned way, meaning that they do not need a transmission to apply necessary torque.
However, some recently manufactured electric cars, such as the tesla,
do have a transmission and needs oil , as creating the right balance between torque and speed can sometimes be difficult without one for some manufacturers.
So whether or not your car has a transmission, and therefore transmission fluid, will be determined by the type of electric car you buy.
You should have learned by now never question your kids on this new stuff and think you are right mine just rolls her eyes and says dad you are 30 years behind the way you think