I think article is arguing that localhost still has cost when onboarding and maintenance cost that is not really that visible because maintenance happen while devs are doing other task - but usually it is included in some task to setup some config.

So I would agree localhost can be basically free, only that company has to keep developers in-house and not burn through 10 juniors each quarter.

If company wants to burn through people like Amazon in warehouses then having cloud dev-env is way to go.

Yep. Most of the people I know don't want to pay subscription fees for cloud services, when their own desktops are powerful enough to run what they're working on.

Just automate localhost development environment deployment.

Which is why it appeals to GitHub / Microsoft. Now you have to pay them for something you used to do for free.

Localhost isn't free, we buy more expensive laptops for developers than any other teams.