[cptskippy]

> Are all EVs that much simpler?

Yes.

Internal Combustion Engines have at a minimum a Combustion System, Ignition System, Fuel Delivery System, Exhaust System, and a Cooling System. These can vary in complexity but, apart from air cooling, any one of those systems will be more complex than an EV's electric power-train. On top of that, most of the parts of an ICE are mechanical moving parts where as most of the parts of an electric motor are stationary non-moving parts.

ICE vehicles almost universally have a transmission gear box that contains a configurable gear system to alter the gear ratio of the vehicle. All EVs on the market use a fixed gear box with a single reduction gear set.

> Is the drive train in a Tesla Model X P100d much simpler than that in a 1.5 NA Yaris?

Yes, dramatically.