The weight savings multiply into even less energy cost in production, as you don't need such beefy suspension where you have a lighter engine, and the engine needs to be less powerful where the body weight is lower, and so on round in a circle

True enough, but range in EVs creates a multiplicative effect.

Design passenger cabin, add suspension, motor and batteries to go 40 km. Light weight (less than comparable ICE by a few kg). Marketing comes in screaming, we need at least 120 km range !

OK, triple batteries, increase suspension and motor size to move more kg. OOPs, with added weight of batteries and other, range is only 80 km. Increase batteries by another 50%, .... closer. One ends up with x6 batteries to x3 range, and almost double the overall weight, but heavier than a ICE car. (VERY rough calcs to make a point).

Other solutions ? Downsize from 4-5 passenger compartment to 2 or even 1 passenger compartment.

One engineering optimization leads you to a "hybrid
car", the eBike. Passenger/motor works with battery (one can afford high tech batteries for such an efficient mode) and a very small electric motor to give extended range.

Another engineering optimization may lead to a 2 passenger titanium EV (titanium, unlike carbon fiber, can be recycled) with fabric seats, charcoal heater, no air conditioner. Expensive structure but fewer expensive batteries. Minimal parasitic loads and weight.

Best Hopes for Adapting Society to Engineering Reality,

Alan