Not sure if they are. There is some anecdotal evidence that Tesla is using it for Smart Summon.
https://teslamotorsclub.com/tmc/threads/tesla-owners-can-edit-maps-to-improve-summon-routes.172027/

I have created a MoreTesla feature request, asking Tesla to use OpenStreetMap for everything.
https://moretesla.com/issues/2pFLc2dHne3HQfyvXuiK