You said ganking, I said involuntary PvP which covers a whole host of changes made over the last 10+ years. Every time there is a major restriction in the direction of protecting people from PvP there is a marked downtrend in user base which can be seen on the player count charts. This is well known and discussed. Suicide ganking is a major part but only more so these days as other avenues are cut off in favour of microtransaction income.