> We have a 2015 MPB that can no longer receive OS updates, because apple reasons
That CPU was dropped from Windows 10 support with 22H2, pretty much the same time that Apple stopped supporting it in macOS. The last build of Windows 10 supporting that CPU reached "end of service" more than two years ago.
Microsoft officially supports Windows 10 22H2 on every CPU supported by previous versions of Windows 10; Windows "Supported Processor" lists are for OEMs building new PCs, not end users updating existing systems.
According to the current supported processor list, the oldest Intel CPU supported by Windows 7 was introduced about 5 years after Windows 7 itself [1].
[1] https://learn.microsoft.com/en-us/windows-hardware/design/mi...