Great map. There might be some categories missing, couldn't find any Katatonia, Agalloch, Alcest nor Tiamat. Alcest and some Deftones are considered blackgaze and Agalloch, Wolves in the Throne Room fall more into grey metal.
I see Tiamat at Goth Metal.
It's interesting because some of these bands are older than these terms. Alcest wasn't considered blackgaze until albums inspired by their own sound became popular, for example.
Metal also has history where a genre is aesthetically defined as well as sonically, which complicates things.