GNOME has no thumbnails in the file picker https://jayfax.neocities.org/mediocrity/gnome-has-no-thumbna...
Clearly this isn't an issue that people care about enough to do anything about, otherwise someone would have gone and implemented it.
Good software design encompasses listening to and talking with users, and actually discovering what they need, where their pain points are, etc. They won't tell you explicitly.
Apart from being a software developer, i'm also a user of course. I use GNOME every day, and even though i'm affected by this, i haven't found the time, patience and dedication to actually go and try to fix it. I understand that the GNOME developers might not have the time either. But it's not like this issue does not exist, or that it's not important.
And if i, and many people who see this as an issue and could potentially fix it, don't do it, then how can we expect that non-technical users would?
I have tried to teach my mother how to copy files between devices countless times in Windows. It's not an easy task for someone who hasn't grown using a computer. I'd love to advocate for more people to use Linux, but i won't, because each little thing like not being able to see the image whumbnails when picking files can be a road-blocker for non-technical people, and add up quickly.