Reproduction steps:
1. Open the attached “BugRepro” project
2. Build And Run the Player (File > Build And Run)
3. In the Player, press space bar on the keyboard
4. Wait until a message is logged at the top left of the screen, that the scene is loaded and observe how long the loading took
5. Press space bar again
6. Wait until a message is logged at the top left of the screen, that the AssetBundles are unloaded and observe how long the unloading took

Expected result: The loading and unloading times are roughly the same
Actual result: The loading time was around 7 seconds, while the unloading took around 139 seconds

Reproducible with: 1.21.12 (2022.3.7f1), 1.21.21 (2022.3.34f1)
Couldn't test with: 1.21.21 (2021.3.39f1) (missing Scripting API), 2.1.0 (6000.0.7f1) (Couldn’t build Addressables Group)

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Note: The times may vary on different machines