Hello @YoinkerBoinker, this is the current expected behavior for most Linux native titles.
In the interest of long term maintainability for all older Linux native titles, Steam will use the Steam Linux Runtime 1.0 container environment by default. Steam is accurately reporting that the runtime environment is being used with the game.
Nothing extracted yet.
Your system information
Please describe your issue in as much detail as possible:
Steam claims that a certain runner was selected/forced by user although nothing was selected or forced for the game (nor globally)
Steps for reproducing this issue:
Just check out my screenshot