Can display configuration changes conflict between user accounts?

Yes. BetterDisplay saves each user's app preferences separately, but System Configuration and Flexible Scaling writes display overrides shared by the Mac. Applying a different configuration from another account can replace the override created by the first account.

For the underlying rendering method, see what flexible scaling and custom resolutions change.

Choose one account to manage these system-level edits: custom resolutions, flexible scaling, native or default resolution overrides, the system display name and the display's TV or computer-monitor role. Make subsequent changes from that account so there is one consistent saved configuration to apply.

You can still run BetterDisplay in the other accounts and use their own app preferences. Avoid applying a conflicting system configuration there. Merely switching accounts is different from applying an override. It does not mean that every setting is automatically overwritten at each login.

If modes change after someone applies settings in another account, review the intended configuration in the account that manages it, apply it again if needed, and follow the app's activation or restart instructions. Configuration Protection cannot recreate a mode that the active system configuration no longer provides.

Overrides also apply to all displays with the same vendor and model identifiers. See shared model settings for that separate scope rule, and System Configuration for the edits and Apply workflow.