Comment by avidiax
I have heard anecdotally that auto manufacturers are sensitive to a price change less than $5/vehicle. This is better than some industries that are sensitive to $1.
What could easily have happened is that the negotiators didn't include A/B updates in their spec, or they only specced A/B updates at 1GB OTA size.
They do their usual hammering on price, and the head unit or ECU manufacturer gave them some savings by cutting storage space to the bone.
Maybe it was still enough for A/B updates, until the usual software bloat took the updates past the critical limit.
They could still do a safe update by doing an A/B/A update (where B is a shrunken, update-only OS), but that requires development time, and the engineers should already be working on the next vehicle.
Worked for them. Corporations with many brands in their portfolio might discuss for weeks over price differences of components of 0.20 Euro. That‘s twenty Euro cents difference for e.g. a USB connector. If you expect that a vehicle platform sells in the 10s of millions over its lifetime, you‘re talking real money very quick!