After installing Arch Linux and some of it’s variations i can confirm that my WiFi 7 module, a ‘Qualcomm FastConnect 7800 Wi-Fi 7 High Band Simultaneous (HBS) Network Adapter’.

That sentence is incomplete. Did you mean to write something about the adapter there, or are you just confirming its official name?

The damage done to the module has left it’s WiFi 7 capabilities dead and Windows even rejects the 6G connection of the router.

How do you know the Wi-Fi 7 capability ever worked in the first place?

This is unacceptable and there is no warnings, compensation or support.

If software (the driver) actually caused permanent damage to the hardware, one might ask why the hardware/firmware allowed it. Perhaps the hardware maker should be compensating and supporting you?

Have you considered that this might be a firmware problem, and might be fixable?

Therefore i have had to begin using Windows as it is the only ISO which will now boot into the installer.

How in the world would a wi-fi adapter's lack of connectivity prevent you from booting an operating system's installer image?

Whatever it is you think you've confirmed, you might want to detail what you observed to reach your conclusion. (Once you're no longer so upset, that is. It's hard to communicate clearly when stressed.) Without details, nobody here will be able to help you.

I’m really upset by this and I now need to spend £360 on a new motherboard.

My condolences regarding the terrible experience. For what it's worth, the built-in wi-fi on some motherboards is a replaceable module, sometimes hidden under a hood. If yours is such a board, it's possible you could just swap out that part instead of buying an entire new board.

If you still decide to buy a new board, I suggest choosing one that's known to have support for whatever operating system you intend to use.