macOS Monterey version 12 is a stable, lightweight upgrade that works great on older Macs, and you can use the direct DMG or ISO links to download, install, upgrade, or downgrade your system easily.

This used to be so easy; download an installer, save it to an external drive, use it on as many Macs as you'd like. Not anymore... I’m trying to update my wife’s MBP. This is an employer provided ...