Why FOSS OSes often don't have power management as good as proprietary ones

(Especially Haiku.) It may seem odd but it's not. Haiku is a recreation of a late-1990s OS. News for you: in the 1990s and until then, computers didn't do power management. The US government had to institute a whole big programme to get companies to add power management. https://en.wikipedia.org/wiki/Energy_Star Aggressive power management is only a thing because silicon vendors lie to their…