I had the same disk auto-eject issue but after many trials, seemed to get this configuration working as follows: MacBook Pro 13 2017, 4 Thunderbolt 3 port. OS Monterey 12.2.1. An External HGST G Drives 4T with Thunderbolt interface, Mac OS Extended (Journaled) formatted. Another External HGST G Drive 4T with older USB interface, APFS formatted, used as a back up drive in Time Machine. This drive connects to the MacBook using an USB to Thunderbolt adapter. Energy saver: Enable Prevent computer to go to sleep when display off. Disable Put Hard disk to sleep .... I never had problem with the HGST Drive with the Thunderbolt port. But I kept getting Improper Disk Eject error message with the older HGST Drive with the USB port when it plugged in to the right Thunderbolt ports on the MacBook. Problem seemed to go away after I plugged it in the left Thunderbolt ports on the MacBook. So far I was able to run Time Machine again using this back up drive. Interface/Compatibility issues?