I have a little more cynical take on Tesla’s announcement. I think it’s a play to get other auto makers reliant on Tesla’s infrastructure as a way to:
1. Give them scale to build charging stations and batteries
2. Make electric cars more compatible so they can grow the pie of electric cars vs gas cars (rising tide lifts all boats)

The car business is a scrappy zero sum fight. Tesla is in the gas station business. Or the electric car equivalent: batteries and charging stations

A shrewd move, not an altruistic one.