"It increases cost, limits non dealer garage/diy work, causes distractions and ties you in to manufacturer/dealer use."
I think you just answered your own question. This is a follow on from trying to restrict the access to the service management software and keep you buying vendor parts. They make less and less selling the actual cars but the margins are in repairs etc. The cars are actually breaking down less so the parts scam gets worse. Don't forget that compliance and all the safety nanny's are being pushed in by the governments as well.
It's called feature creep. A has feature 1 so B must have it.
Sub-system suppliers that do the integration want to flog all parts to the vendors for better margin on their development work.
