Windows source is open to most people at Microsoft IIRC, so I’m not sure why you’d pay 500k for that...

If that was true, I am pretty sure that the entire windows source would be all over the internet.

Disclaimer: Am Microsoft.

Windows source is open to most people at MS. MS is not joking when it says we practice an "inner source" policy, in that we do not rely on the security of our source code to secure our products.

My question then is why is windows not just open source entirely?

Be like Red Hat where the OS is open but you pay for support, I don't know why that model wouldn't work for MS.

Not OP (and not Microsoft), but I would say it's a complicated road to get there.

I do believe we will see open source Windows in... the next decade?

Anyone want to take a longbet with me? ;-)

I am willing to add to the pool, I am also betting core components of Windows will be open sourced soon.

I'm betting more on "replaced". E.g. When they switched to Webkit, they didn't opensource Trident. How many people would notice, if the next version of windows used CUPS running on the WSL2 backend with a nice small GUI in Windows-Land? The very informative comments from @zinekeller and @ChrisSD highlight the problems with opensourcing mixed-vendor heterogeneous code bases. Also open-sourcing code rarely means it becomes "maintenance-free".

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