I don't think it's particularly common for techies to upgrade the screen, just that they are the only ones who would because... well, upgrading a screen usually isn't ever needed. The only reason I did is work was offloading some good laptops for low cost but they had sub-1080p screens. I took one with a broken screen for free and when I did the replacement I used a higher end model's replacement part.
I.e. the only different part is finding a laptop of the same screen size and eDP (embedded Display Port) generation to select from. The rest is the same. If you've already got a good screen it's usually not possible though as you're limited by the eDP generation's speed instead of the panel.
I can't even begin to think about how a laptop screen upgrade would go. Who's manufacturing them? How do I get just one? How do I make sure I don't spend a month waiting for shipping and get a fake? How do I make sure the housing is going to fit right? How do I make sure the pin outs match?
... and etc etc. An official upgrade pathway eliminates all of that. Sure, it's not bringing you back to "average person", but Framework have been super clear that's not who they're after. They want people in my bracket. To be honest, as a cohort, we've proven we're willing to (over)pay for this kind of thing, too. It's why the PC Market still exists despite graphics cards being overpriced by about double.