Can BetterDisplay change the image while an XDR reference preset is selected?

Yes. A reference preset defines the display's reference behavior, but separate software dimming and image adjustments can still change the visible result. Applying those adjustments does not rewrite the preset itself.

For work that needs the preset's unmodified output, open Settings > Displays > [display] > Image Adjustments and turn off Enable software-based video adjustments. This disables BetterDisplay's software dimming, color-table effects and overlay/compositor adjustments for that display. It also disables software brightness upscaling and changes how combined brightness works.

The output then follows the reference preset and any native brightness adjustment that preset allows. Selecting a preset does not calibrate the panel. If measured brightness or white point differs from your target, check the preset and display calibration.

See Image Adjustments for the master preference and Presets for reference-mode selection.