I haven't built or marketed anything myself but i believe if i understood correctly from several folks who have that vga was a cheaper choice due to licensing costs for dvi or hdmi at the time.
Not sure if vga is past that point or open but when keeping home brew kits cheap for us hobbyists every dollar counts. It would be interesting maybe as a Wikipedia page (thought there was one) to show which projects were out there and preferably which are still active. A shrinking but understandable issue when buying im batches with personal money in hopes that theyll sell eventually.
