While Apple has moved on to APFS file systems and Apple Silicon chips, the InstallESD.dmg remains the key to unlocking the Lion era. Whether you retrieve it officially through the App Store or via an archived backup, understanding how to manipulate this DMG file allows you to preserve the history of Mac computing.
Before you click download links, you must understand the anatomy of a Mac OS X installer. mac lion os x 10.7 - installesd.dmg download