[wolvoleo]

Yes but they can force new versions with limited functionality. Like when they deleted half the music from GTA San Andreas.

On GoG you can choose to install every older version they've distributed (though GTA is not on there obviously)

[augusto-moura]

The GTA case is because js technically an update from Rockstar, not specifically Steam's fault here. There are always to downgrade a game, but true, it is not as easy as GoG.

[wolvoleo]

No it's not steam's fault but they do allow it to happen.