If this was a solvable problem. I'd love to solve it!
Because honestly it really does seem like starting with a different install would fix it. But if he gave up on fixing it , then there's nothing to solve , it's just a rant , but not a justified rant. Even as a windows user and a linux hater I know windows as a whole is worse but it's definitely not because one machines gpu isn't working.
And from the sounds of it , 10 only had an issue with scsi and your wireless? am I to assume that means just using windows 10 fixed the gpu problem and left you with two much smaller problems?
Let's be fair and consider we are a minority concerned about video card compatibility, yes I know you're talking about the rx480.
The majority of users are trying to connect to their WiFi or setup an all in one printer scanner copier. I had to modify some acpi settings for my backlight to function. All new laptops are tried against windows, fewer people use desktops these days.
Let's not discount the features for the most basic of functionality. People buy an rgb keyboard to change the colors, not to install a second OS in order to maintain those features.
Things are always improving and I agree, at an astonishing rate. But I'd be willing to bet if I built a cutting edge PC there would be some bullshit in grub that would need to be added/changed/removed.
I know a few people still running GTX580s and are just happy as can be, some people run hardware until absolute death. (I do this, but I have GTX680s lol)