They have almost 0 computer market share in developing markets, nobody knows how to use apple, nobody knows their stack and their programming languages, all the infrastructure is built around windows.

With smartphones it's not such big a problem cause you don't do anything productive on smartphones anyway.

With PC/laptops it's a big disadvantage I don't see changing in a few years just because of small performance advantages, even if the prices weren't an issue.

This depends on the use case. For phones and consumer applications, the walled garden is often tolerable. But imagine trying to run a cloud service, a FinTech system, a factory, an ERP system, etc in the walled garden.

Not as long as Windows is not a default OS.