[cloudify]

Probably because EV trucks would need to go through the current Brenner motorway, that is a very trafficked road, from Wikipedia ( https://en.wikipedia.org/wiki/Brenner_Pass#Motorway ):

The ever-increasing freight and leisure traffic, however, has been causing long traffic jams at busy times even without border enforcements. The Brenner Pass is the only major mountain pass within the area; other nearby alternatives are footpaths across higher mountains at an altitude of above 2,000 metres (6,600 feet). As a result, air and noise pollution have generated heavy debate in regional and European politics. As of 2004, about 1.8 million trucks crossed the Europa Bridge per year.

[nick238]

There's an alternative to only on motorways and never on motorways: sometimes on motorways.

90% of the time you can use ordinary roads, with autonomous driving acting like a normal truck, giving the meat bags plenty of space. The most congested 10% you can build restricted access paths only for your smart trucks where they can act more like a train, with minimal spacing, increasing the traffic capacity of the road/tunnel/bridge/whatever so the extra cost of constructing it pays off sooner and/or it's cheaper in the first place because it's not built for drivers so doesn't need to be as safe.