surely a company is absolutely incentivized to share these priorities?

every accident is a hit to their profits and pr.

No, because they can benefit even more from recklessness than the expected profit/PR damage. Someone already mentioned Tesla, but there is also the Volvo emissions scandal, Boeing's safety failures, and many more examples.

At the extreme end, picture a company that manages to get an okay from the city of SF for public testing, but whose internal tests show there is a small but significant risk of serious accidents and the product needs another two years of development to be safe. Their funding runs out in one year.

What do you think they would do?

I think Tesla has shown this fairly clearly to be untrue.

It takes a hit if there isnt' a very solid marketing/pr/charismatic leader to distract