monterey toolbar
Every space has its own toolbar decor. Setting Light/Dark/Translucent has no effect on toolbar (does affect windows) 1 is white, 2 are grey, 2 are translucent (grey blended with background)
Is this fixable ?
macbook pro 2019
Question marked as
If by toolbar you mean the Menu bar at the top of the screen, then its somewhat smoked glass translucent by default and will change with whatever background is set on the different spaces. Change the background wallpaper and the menu bar will change its color to match it.
There are not controls except to reduce transparency in System Preferences->Accessibility->Display->Reduce Transparency. Then the menu bar will take on the window color. Light or Dark.