This has to be just an error the web designer made. Probably copied and pasted old info then added in the new stuff and missed the OS support/
I'm playing Serious Sam 4 right now. It's suppose to be locked to Win 10 but it's running fine on Win 7. I'm using an Nvidia card and Vulcan.
Some people will give up AMD before they give up Win 7
I just checked. There is a Windows 7 driver for the RX 6800XT. I am using the latest Adrenalin 2020 driver on Windows 7 for the RX 5500XT myself right now. But I am using an older Radeon Settings because I think the newer ones stink.
Not only are there drivers, they are WHQL CERTIFIED...
But the current Radeon Settings software iteration is so bad it is not usable for me.