Why? If you know you'll play it it's only $30 now, almost certainly higher at release. The Early Access is running great for me (on Linux no less) and the closest thing to a "bug" I've found so far (3 hrs in) is that some of the voiceover doesn't 100% match the written text.

Seriously, it looks and feels excellent already. My understanding is that only a few biomes are finished, and they'll release more over time. But even the story beginnings are already solidly in place.

the game itself still gets updated. download pirated game -> update drops -> wait unil someone uploads it -> download latest version

If its too niche you might have the situation where nobody uploads the updated version and waiting will just get you the same version as if you didn't wait.

repacks will generally use patch updates but I find it's easier and less bug prone to just use a steam emu or patched steam and just replace the steamapps/common/game folder each update

Pirated copies get updates just like any other. They just don't get automatic updates, like most storefronts provide. That's a feature of the store though, not the game.