Few things I'ma try to summarize:
1) Login congestion is different than server congestion. How many players are logging in is different than how many players are already logged in or how many characters are already created on that world and semi-active.
2) Feedback that is "I don't like this feature doing what it was intended to do" is not helpful to developers. You not visiting/interacting with people on other Data Centers unrestricted is the intended goal. That is the equivalent of someone punching you, and you tell them that it hurts and they need to not do that. That was the goal. That is why they punched you to begin with. Hell, that motivates them to do it again. There's no obliviousness that punching leads to hurting you, there's no obliviousness that shutting down travel leads to social and raiding restrictions. These are not unintended consequences.
3) What you should be saying is "This is the goal you had, this method of achieving it has these negative side effects, here's this other idea that achieves the same end goal without those negative side effects." However, half the forums seem to have not kept up with lodestone messages and interviews regarding this subject.
- Cross-DC Duty Finder is not a realistic option. They already said this is 3 years of full force development time if it's even possible. They do not want to take this route because it is not a good business decision. Those resources could be spent on other things and should it fail or have unintended negative consequences, could become years of wasted development time. And they/we do not want 5-6 years of messed up population discrepencies, a solution needed to be soon.
- Incentives to play on other Data Centers are not a realistic option. They do not want to shift where the majority of players are playing to one location. Trying to find incentives that drastically create population differences that you can't strip away from people later, that don't break the game, and can be applied to multiple data centers is a headache if not impossible as opposed to just forcing people where you need them to be.
They already stated they've already discussed these internally and pitched around ideas and none of them they liked. So unless people find an alternative that the devs couldn't, that is viable for them as a business, we are not getting reversal changes.