As for the permission popups, they have already done that through XDG Desktop Portals. You might have noticed that, for example, apps with supposedly no filesystem access can still open files you selected via the file picker or opened via the file manager. Or that apps need you to explicitly allowlist them to access your location data. Those are apps that use the portals permission system. Unfortunately not all apps use portals yet.

I have seen mockups of GNOME adapting a similar banner style as what Flathub. We might have to wait for GNOME 47 though.

Here I am chilling with Amberol

I vaguely remember some money calculating-related project guy who received a PR that heavily optimized and updated the project. Since he was very busy and no longer really wanted to maintain the project, rather than reviewing and merging the commit, he gave the contributor complete access to the repo for them to maintain the project at their own discretion. The project was unpopular back then—when he looked back a few years later, he was surprised to discover that the project had racked up several thousands of stars.

BlueBuild and deploy your customized image to the devices

Rufus has workarounds for the mandatory login.