I wish companies didn't have to be so freaking careful about what they say nowadays. The slightest misstep could lead to a lawsuit. So, when things like this happen the company won't make an official statement. (Better to say nothing than get sued or end up causing bad PR. See Yooka Laylee.) But, of course, by making no statement the customers just get frustrated at the problem and the lack of acknowledgement from the company.
So the rumor goes, the reason for this is server performance drops due to the service. Though, I have a very hard time believing the game was allowed to run below optimal performance in its first year. (You know, when people decide if a game is good or not.) Either way, if this is the case then there is no true excuse to end the service. Its simple, for 1-2 days per month have a preadvertised period. (Through in game mail) Offer the service during this window, preferably not overlapping any portals, community challenges, rux, etc. This means everyone can use the service and will be warned when it is coming. If you miss one month you can just do it next month. The loss of performance (if it is really that significant) will only occur for a short time and still resolve all of this frustration.
Now, tin foil hat time. I personally believe the decision came from above due to the additional costs to run such a program continuously. This is only a hunch, I have no definitive proof of this. But, given the revenue that can be gained from GW1 it would seem like a strange business move to cut the transfer completely. Of course, without access to hard numbers this is only a guess. Maybe GW1 is far less played than my estimates. If it was truly technical issues and they really wanted to continue it they could find a solution. People don't often fix what they don't see as broken. /time foil hat time
