Steam used to have a way of backing up installs yourself; if it’s still a thing, I have no idea where it’s hidden now.
Library -> Game context menu -> Manage -> Back up game files...
The game files are just directories you can archive however you want anyway. No stinky 'installer executables' necessary. (:
Library -> Game context menu -> Manage -> Back up game files...
The game files are just directories you can archive however you want anyway. No stinky 'installer executables' necessary. (: