I would argue that the whole "new NA datacenters" thing was more about freeing up instance servers more than anything. NA got no new world servers out of the deal. Free transfers, preferred/congested, population balancing. While some of the current issues may indeed be player-induced, it's a straight fact that there are times when all NA servers are locked to new character creation. That's just not a good thing to have during your big expansion launch hype.

I'd even argue, anecdotally, that with the data center split, worlds seem like surely they must be smaller now. Maybe yes, we've had a big influx of new players or something and legit everywhere's pushing full at times. But part of me wonders if it isn't a sort of throttling issue on SE's end, deliberately restricting capacity so things don't break like they once did. No breaking is great. But it's not great presenting new players with a locked door, with rather suboptimal options to getting through/around.

I was on Mateus back when 4.0 launched. At the time, Balmung had only just been locked, and the organization to set up Mateus as the next RP server was still pulling itself together. At the time. Mateus was the dead server. It was the world you'd often hear players (typically Balmungians) suggest "just merge this one to make more space." I can remember hitting one queue of about 200 near 4.0 launch, and never really anything else until the population finally exploded.

So, anecdotally, now, as seemingly every world (I assume) isn't safe from login queues, either we've got way more players (possible), or capacity is reduced to ease strain. Idk. Just my own conspiracy theory.