LOOT is definitely not anything new. I’m decently confident it’s been a thing for over a decade. To clarify: load order is important to make sure no incorrect files or assets are accidentally overwritten in the course of loading the mods onto the base game, as an incorrect load order can cause a lot of issues.
Regardless, it looks like there is a Linux compatible flatpak version on flathub. Here’s the GitHub page. I personally can’t say I’ve used LOOT on Linux, though, only on Windows, as my Skyrim modding days came before I made the switch, so your mileage may vary.