Update: Amazon Games are now increasing server population capacities:
Population Caps (Source)
We are now increasing server caps for full regions, but please be aware that game servers have a finite capacity and we are working to ensure server stability as we allow populations to increase....
(On the free to play launch implications)
Yes, this is top of mind as well and being considered as we continue to make changes today.
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Server queues are most prominent on a specific selection of EU servers; there are still additional servers both on EU and across other regions that have no queues.
Many players have been running into sever queues since launch and Amazon Games have now commented on the matter, stating that they are increasing server population caps and adding new servers. You can check out the servers' statuses here.
Server Populations (Source)
We are in the process of increasing population caps now.
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Sever population caps are not infinitely unlimited, unfortunately
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We are opening a new server for the EU region
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Please be aware there are also servers available in each region that do not have current queues
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While you may experience queue times on some servers as they begin to fill up, please be aware that there are servers in each region with no or low queue times that you can join if you want to get in-game and enter Arkesia more quickly!
Source: News Latest Topics https://www.icy-veins.com/forums/topic/64098-lost-ark-server-queue-times-population-caps-new-servers/