The Highlanders are testing vehicles: https://zoox.com/journal/autonomous-zoox-testing-vehicle

You don't make breaking changes. You provide the new API and the old API at the same time, and absorb the additional complexity as the library owner. Best case scenario everyone migrates to the new API and eventually remove the old one. This sounds onerous, but keep in mind at a certain scale there is no one commit in production at any given time. You could never roll out an atomic breaking change anyway, so going through this process is a reflection of the actual complexity involved.

Because they make more money using their servers for their own products than they would renting them to other people. Meta has an operating margin of 41% AFTER they burn a ton on Reality Labs, while AWS has a 21% margin with more disciplined spending. Social media is a more profitable business than infrastructure.

That's not universally true. The sewer system in my town was overbuilt in anticipation of a development that fell through. That's why sewer / water bonds are typically up for vote separately from property taxes because there's such an interplay with development.