i could be totally off the mark though
No, it's for money.
It's the charging stations. There aren't enough of them, and it's the biggest problem they have.
Tesla needs the big manufacturers to build electric cars so they will put charging stations everywhere.
There may be altruism and mission involved, but Tesla isn't (and shouldn't be) a charity.
Altruism and being a company are not mutually exclusive. In case of Tesla, being a company is probably the most effective way to achieve its goal. It's the difference between instrumental and terminal values I'm trying to point out; i.e. Tesla is earning money to electrify transport, not building cars to earn money.