Mac gamers still running macOS version 11 will need to upgrade to at least version 12 if they want to continue playing titles purchased via Steam.
Valve has announced that its Steam Client will stop supporting version 11 from October 15th, citing the fact that some of the app’s core features “rely on an embedded version of Google Chrome, which no longer functions on older versions of macOS”.
In a support note it adds that “future versions of Steam will require macOS feature and security updates only present in macOS 12 and above”.
Apple ended all security updates and support for macOS 11 in 2023.