Yesterday, July 1st, they announced the Alpha release of this next-generation mod manager and their new Product Manager got in touch to mention they “would be really keen to get feedback from Linux users”. So this is your chance to ensure Linux (and Steam Deck) finally become a first-class citizen for game modding.
It might take a bit to wade through the BIOS settings to get it up but I’d recommend a process of elimination based on “Doesn’t sound relevant to the boot sequence” to figure it out. I have a recent HP laptop and I installed KDE Neon on it.
Searching for “How to install Linux on [your BIOS and version]” might also help.