Comment by SR2Z

This is what Tesla does. Elon Musk has been selling FSD for more than 10 years and a huge chunk of Teslas have computers too old to run the current best model, which IIRC is already transformer-based.

Because having to offer upgrades to so many cars is expensive, Tesla puts a distilled model on older cars that performs worse and has no redundancy.

Time will tell if he can get away with this (hopefully not) but you are describing a system that's near-L4 and already exists today.