Intensity? Are you not getting the actual transparency option? It is exactly what you asked for, it turns the transparency on and off like a checkbox switch.
I did Control Panel\Appearance and Personalization\Personalization\Color and Appearance
I see Change the color of your window borders and taskbar
I click one of the colors > I chose max Color intensity > I save but the taskbar is still not solid
and I DO NOT SEE action center transparentOn or Offlike on you pic above
Pls give full path to it