I don´t know why people overvalue Musk an Tesla that much for reducing emissions. When I ran the numbers last year, a single city in China(Guangzhou) was enough to reduce emissions more than entire Tesla sales, just by replacing all of their busses with electrical ones.
I'd actually argue that the lack of a carbon tax - not its existence - is an incentive, since you're not charging for the negative externality of trashing the atmosphere.
Isn't that exactly what government incentives are for? Subsidize the thing you want to see succeed, until it no longer needs subsidizing.
Of course, that is the ideal success scenario, in the failure scenario, you subsidize the thing until it fails, or until you can no longer afford to subsidize it.
EDIT: grammar
Of course. The point is that it is ridiculous to use Tesla as evidence that the free market will solve our problems when
1. Tesla's impact on global emissions is minimal.
2. Government intervention in EVs has been there from the start.
The charitable conclusion is that governments and markets can work together. The pessimistic conclusion is that markets are only capable of putting lipstick on pigs.
Take those away and the "green" companies would have NO incentive to push their work. They'd be working with people wanting to do better first and foremost, and then they would - ironically - be competing with petrol and energy companies, who also have "green" all over their marketing.
Renewables and EVs could not compete without government incentives.