You don’t own anything you purchase on Steam
Games sold on Steam are not required to use Steam’s DRM. There are lots of DRM free games on Steam. Steam is only required to be installed to purchase/download them but not to run them. After download, the game files can be copied and ran on any computer without any verification.
Unfortunately, my friends play it and I’m often roped into playing it with them. My advice: The game is greatly improved if you disable all forms of interaction with other players. Chat is muted by default now, but I’d also recommend muting pings and emotes. No form of interaction is ever positive in that game.
Even then, their matchmaking algorithm seems to be designed to hand an easy win to one team and just switches up which side you’re on enough times that you won’t quit.