LineageOS, GrapheneOS, CopperheadOS, CalyxOS
All only work on the google Pixel line of phones. I suppose if you buy a used one, you won’t be contributing to google much.
Lineage is available for many different phones, certainly not just for the Pixel line. If Lineage doesn’t have an official ROM for a particular phone, you can still download ClockWorkMod (Lineage’s predecessor) ROMS for just about any Android phone. Fixing do that to my Note 2 tomorrow. F*ck Google.