It is a hard pill to take.
On Endless or Ubuntu you could install Brave in one click but it will be Flatpak or Snap.
Sun is now Oracle anyway.
I you are asking about permissions so yes. I often limit access filesystem paths, dbus proxy, devices and network.
Fediverse is tribalistic like such communities often are.
I use flatpaks mostly. Flatpak dependencies (runtimes) are stored separately from the host system so and don't bloat my system with unwanted libraries and binaries. App data and configs are stored separately and better organized. Everything runs in sanboxes. I use overrides extensively. All these are very convenient for me.
As alternative to the RHEL and its clones maybe. But there is no alternative to Fedora in Debian (with exception to Ubuntu and derivatives) family, even Sid consists from outdated packages.
To go x86_64-only was a mistake for Arch. Distros like Fedora or Debian, or openSUSE have universal building systems and infrastructure for building packages for different architectures. Arch just creates unnecessary fragmentation for the GNU/Linux landscape: software need to be packaged for the distro and for the same time PKGBUILDs cannot be reused in general for anything to go full Arch Linux. Not for other architectures, not for servers or LTS. Only for a x86_64 desktop niche. Arch Linux doesn't scale.
BTW I use GNOME without any extensions.
Shattered Pixel Dungeon
A good part of the fedora immutable spins that they are just base systems for running flatpak apps and if you use apps as flatpaks what distro to use as a base system doesn't matter much. Even immutability is not such a big deal as the separation between the base system and the applications. It is less about tech and more about usage habits.
As a flatpak user I can call myself a distro nomad. I've switched from Silverblue to Debian now. If you use Kinoite you can try KDE Neon + flatpaks or openSUSE Kalpa (their immutable variant with KDE).
I doubt that current systems can replace cash at scale but for niche usage Monero and Litecoin. Also Grin but it is dead.