but Steam is also kinda weird about this. Shadow of the Tomb Raider for example (at least the definitive edition) installs the soundtrack automatically as a DLC:
https://steamdb.info/app/849165/
But it doesn't list it on the game's page:
https://store.steampowered.com/app/750920/Shadow_of_the_Tomb_Raider_Definitive_Edition/