I feel like they’ve got couple of things wrong or they base of outdated information.

The packaging, yeah it’s still a mess if you absolutely have to put it in a native system package, but building something like Flatpak would generally be better. Or just build binaries against some common runtime like Ubuntu LTS and other distros will figure out, there’s really not much more here. It really sounds like someone wrote it in 2000’s about all distros being completely different and it’s expected to fall apart if you attempt to run it on say Fedora. They’re really not that different today. Also, universal package formats exist.

They completely skip XDG desktop portals that can provide at least huge chunk of functionality they need. There’s really no need to talk to GTK or QT directly. simply require portals and use its function for choosing file or directory. That’s it, you’ve got native file picker that also works in sandboxes.