Should we still keep old profile fields of defunct services like ICQ, Skype, Yahoo Messenger?

I noticed MSN was removed sometime after 2011 when i last seem to have spoken about it. 

Since they already exist in the database, i suggest you leave them there as artifacts and only make them accessibe via an extension for whomever wants to keep them. I dont see why we should have them in the main phpbb version anymore by default.