Is there ever any advantage to choosing a filter option from the Extensions/Raster menu when the same effect can be found on the Filters menu?

Like, any difference between Extensions>Color>Grayscale and Filters>Color>Greyscale?

Of the commands that appear on both menus, the Extensions/Raster versions seem to be inferior. Either the dialog box has fewer details, or there's no dialog box at all (or in some cases the effect just doesn't happen).

From what I read the Raster menu is only for bitmaps whereas the Filters menu is for anything. I did an experiment to see if maybe the Raster option produces a smaller export file size vs the Filters menu but that doesn't seem to be the case, though it's tough to compare apples to apples with differing dialog boxes...

They do different things.

The items in the extensions -> Color menu change the color data in the selected vector objects (loses data that was there before).

The items in extensions -> Raster edit the selected raster file in the background and replace it (loses data that was there before).

The item in the filters menu puts a filter above the selected objects, like a pair of sunglasses, but the color data is not changed (manipulates data during rendering).