Well because of money. You certainly have to pay to get Ubuntu certificated. And you only do this to have a Linux system with support from the manufacturer.
It's an enterprise problem with an enterprise solution.
The normal personal systems are not in the same segment.
Wish we had that in Germany. As great as the autobahn is, when it rains it reflects so much that you don't see the Markings anymore without highbeams.
But maybe that's a northern thing.