Windows XP sold for $200 in 2001. In 2025, that's $364[1]. If we can find enough people willing to pay $364 for an OS that values privacy and doesn't push needless upgrades, that'll be a start. But XP itself was probably priced based on the belief that people would be upgrading in a few years to Windows Vista. So we might need more than that.

[1] - According to minneapolisfed.org, which uses the official economist-approved inflation rates. Not that I'm implying that there's anything wrong with that. I have all of the orthodox beliefs about inflation that a good citizen should have.