For me it is very useful. Making documentation is much simpler and faster now.
Until there were no Plot on All Layers to get documentation files (PCB shape with footprints and references and dimensions on a gray copper background) I had to plot layers separately to svg and then using inkscape put them together with some problems regarding positioning.
I don’t remember exact problems getting them directly from KiCad but I certainly tried and even reported some bugs. I think in V5 I was able to get satisfactory picture (but with problem to get then back to working colors, closing PCB without saving didn’t helped) for top layer but not for bottom. Probably in V6 and V7 it didn’t changed, but I’m not sure.
Now I get pictures I want directly from KiCad. In Include layers I have for example only F.Cu and at Plot on All Layers I have User.comments (I have dimensions there), Edge.Cuts, F.Courtyard.
I still need to use inkscape but only to do fast 3 actions. I have described it here: