this isn’t healthy:

True, but not in a way that SnapPakImage is going to fix.

What about that isn’t “healty”?
You are basically downloading and saving the signing key of docker to the currently recommended place with appropriate permissions, and adding the docker deb-repository, explicitly stating that it should be signed by that particular key.
If you don’t trust docker, don’t add their repo. By the same logic, the Flathub repo is an “obscure repository” too.

Those manufacturers where you can select either Linux or no OS don’t charge extra for Linux.

Is this message printed onto the screen everytime you open zsh?

It might be hardcoded into the config files, e.g. ~/.zshrc.

The Plasma wayland session is now the default option in sddm (display manager login screen). An X11 session can be selected instead if desired. The last used session type will be remembered, so you do not have to switch type on each login.

https://wiki.ubuntu.com/OracularOriole/ReleaseNotes/Kubuntu

The same holds for 25.04.

Wayland should be standard since 24.10.

Edit: It is also in Kubuntu 25.04.
https://wiki.ubuntu.com/PluckyPuffin/ReleaseNotes/Kubuntu

Or install PowerShell on Linux (Microsoft)