neowin[.]net/news/macos-monterey-is-reportedly-bricking-old-macs/
Apple released macOS Monetary last week as part of its annual update. However, many users reported that their Macs got bricked and weren't able to turn on after updating to the latest version of the macOS.
A probable solution has come up on the Apple Support Communities which uses the Apple Configurator 2. The software essentially revives or restores the computer's firmware.