(superfan checking in) -- I still believe the definitive release is the original `realMyst (2000)` (Sunsoft). https://archive.guildofarchivists.org/wiki/RealMyst . If you only ever play one version, that's the one to play. GOG maintains a beautiful version of this (that works well even on modern Windows), but Cyan de-listed it from GOG a while back, so you can't technically buy fresh copies anymore.
Don't mistake this for "Real Myst: Masterpiece Edition", which is (sorry Cyan), not very good. They imported the old assets into Unity for the re-release, and then did some random texture/asset swaps, the lighting and mood didn't survive the import and is all randomly weird -- strongly recommend ignoring this one.
The original release is good if you want the original experience - https://www.gog.com/en/game/myst_masterpiece_edition
And the new Myst (2021/VR, Unreal Engine) release is wonderful and beautiful, but is more of a re-make to modern gaming sensibilities.