Vibrant visuals no longer works on dynamic worlds, it used to work fine but after the update it doesn't work at all. I don't suspect this is an intentional change because why would you do that? Major loss in profits and players if that's permanent because why would anyone buy a dynamic world if you lose the new graphics
From the 1.21.80 changelog:
If you were previously able to use Vibrant Visuals, then that was a bug.