This is a now a touhou board
The problem with this statement is that it implies /prog/ was ever ]not a touhou board.
There are several hundred threads on /prog/ about touhou, starting from 2007 and continuing even unto this very year that we find ourselves presently in.
Interestingly, 2009 and 2011 were bumper years for touhou discussion here. Many of these discussions are also programming related- bringing together the true board purpose (touhou) and the on-paper purpose (programming). This may have led to the casual /prog/ peruser to make incorrect assumptions about the purpose of the board.
Scraping /prog/ and displaying the most popular [touhou,touhous,touhouii,touhouiim] is left as an exercise to the reader.