Not sure if any of those brands try to blast firmware updates over the net with a "push to prod" mentality...

It sounds more like they didn't follow the specific way bosh requires you to use their HW. I highly double VW or others would use Bosh if hacks are required to get them to work.

Updating the software of node are usually in the automotive industry only allowed by trained technicians. Allowing the updates to be done without turning in the car so a shop is the big difference. Software update in is complex and hard and error prone, for quirks like the bosh stuff here. Many of the big players see it as almost impossible to try to do as Tesla and have it done at the users home.