Most Gnome developers, I suppose, are on RedHat payroll and are not teenage.
They are busy working on various things, this is certain, and these things are apparently more important for them. Like, well, GTK4.
I suppose most Red Hat customers are corporate, and when they ask for featureful Linux desktop, they likely mean playing nice with corporate systems. This is why Evince is such a good PDF viewer, compared to a lot of others; it can even fill in forms. This is why the file chooser without image preview is fine as is for corporate use, because I suppose that 0% of graphic designers choose a Linux machine in a corporate setting.