If your project is on #UnrealEngine 5.5 and you do not plan to update it to 5.6, you might want to cherry-pick Epic's CL 40762249.
(On the non-public Unreal Github: https://github.com/EpicGames/UnrealEngine/commit/5dd153f92b4f0ae3f68fb33f5af4d1481738d4bc)

Without it, applying GameUserSettings can cause a severe RAM usage spike. In one of our our projects that spike was over 300 MiB.

It's only used for a single frame, but on platforms without swap space (e.g. consoles) this might be an issue.

#GameDev