Every time I tried to enable the device auto mount on my second hard drive, it never worked. I always had to manually mount it through KDE's GUI whenever I wanted to access it's content.

I later researched and found out that I could edit the /etc/fstab file with my second hard drive's UUID, which caused it to always mount on startup as I wanted.

So my question is, why doesn't KDE auto mount also replicate this process of editing the /etc/fstab?

The KDE auto mount never worked on plasma 6, I believe it's something related to wayland (even though I don't understand how they could be related).