Linux, Windows and Mac are all comped. Since Linux is difficult to comp as a whole, it is still possible to build an OS that isn't comped, IF you know everything that is comped. This is unfortunate. Even the BSDs have had some level of being compromised.
However you can just go in a weird direction and skip them all into fringe operating systems like Haiku or yes, TempleOS; or even ShrineOS, which unlike TempleOS has networking.