This is a bit overhyped.
No, it isn't. If anything it's the opposite.
Under X11, any program of any kind can see the contents of another program.
Under X11, any program of any kind can see all your keypresses, whether the app is focussed, unfocused, minimised, on another virtual desktop. Anything.
Under X11, any program can inject keypresses into any other program.
Under X11, any program of any kind can access your clipboard.
And it doesn't even take root privileges. That's just the default.
The X11 system itself runs as root, though. And this opens the door for privilege escalation exploits.
That's before we even consider the devs themselves saying that the complexity, decades of spaghetti code, and unfixable bugs make it virtually impossible to patch.
X11 is a security nightmare of epic proportions. An absolutely cataclysmically insecure system. And it's one of the main reasons that X11 devs abandoned it for Wayland.
WTF? Things that run as root, do. Things that don't, don't. Obviously most things don't.
I never said that things that don't run as root run as root. That doesn't make sense, it's self contradictory.
What I said was that install scripts for repo packages always run as root. And therefore anything that makes its way into the script will be executed with root privileges. That is a risk.
For your own user, so what?
What do you mean, "so what"?! A non-root program being able to highjack system commands and even gain root access isn't "so what", it's a glaring security hole.
Actually it is. One can make levels over levels of isolation, sandboxes and more sandboxes, but in the end conscious hygiene matters most.
You're right, but you're taking my words there a little too literally there.
When I say the problems aren't insurmountable I mean "with effort, a lot of these will be fixed and your system will be pretty secure", not "one day Linux systems will literally be unhackable, and no exploit or security issue will ever be found again. Security problems will be a thing of the past."