The most recent information from Steam indicates that, as of September 1, 2023, Steam will no longer officially support macOS versions 10.11 (“El Capitan”) and 10.12 (“Sierra”).
Steam claimed that it made this change because core Steam functionality relies on embedded Google Chrome, which no longer functions on earlier versions of macOS. In addition, macOS 10.13 and later versions of Steam will require new features and security updates.
In 2018 and 2019, Apple is said to have stopped providing technical support and security updates for macOS 10.11 and 10.12. When connected to the network, machines running this operating system are susceptible to new malware attacks. Change to the latest version.
It has been reported that Steam will no longer provide support for Microsoft Windows 7, Windows 8, and Windows 8.1 systems beginning on January 1, 2024.