Why can't I enable the DyAc / DyAc+ and Freesync Premium function / Adaptive-Sync at the same time?

Specification  /   2022-11-11

These features are not compatible. 

When the DyAc / DyAc+ function is on, the FreeSync Premium / Adaptive-Sync will be disabled; or  DyAc / DyAc+ will be disabled when FreeSync Premium / Adaptive-Sync is enabled.