EDIT: Seems to only be an issue in the mirror, actually looking down lets you see the toggle working correctly.
If a WD On Toggle is false when the avatar is loaded, it can be toggled normally.
If an WD On Toggle is true when the avatar is loaded, it cannot be toggled manually, it sticks to whatever is in the true state of the toggle.
  1. Have any toggle written in a WD On workflow. (Single Layer or Blendtree, doesn't matter)
  2. Have its parameter saved.
  3. In-game: Activate the toggle.
  4. In-game: Reload the avatar by switching to a different one and back.
  5. The affected properties of that toggle stick to the on state, even though it should not. Example: Mesh stays active even when toggle is disabled.
This issue existed since the last open beta for 2023.3.3 and just now got merged into live. It didn't happen before that. I assume some “optimization” you did in that patch causes that issue.