Did you upgrade its firmware?

Same workaround works here as with dirty frag. Just disable those kernel modules.

I would use Ubuntu LTS (free) or Redhat Enterprise Linux. If paying is not an option, some RHEL derivate would probably also work.

Care to elaborate how Ubuntu failed newest release?

Systemd has already won. So other init systems must adapt, and modify themselves to be compatible with systemd.

You are trying to install wrong versions of nvidia drivers and proton app.

For nvidia, use this https://linuxconfig.org/how-to-install-nvidia-drivers-on-ubuntu-26-04

For proton vpn, I assume you are trying to install app meant for 24.04. Do not do that, just search one for 26.04, if it is available.