Dauntless' Twitter account has announced that it's "slowly but surely increasing [the game's] capacity" and that it will continue working on its services over the weekend.
Dauntless is the first game to launch with true cross-platform play for the PS4, the Xbox One and PC -- and clearly, people want to live in that ecosystem. While it's unfortunate that some players had to wait that long to get in, the warm reception the game received and the issue it caused prove how much people are clamoring for cross-platform titles. If Phoenix Labs plays its cards right, then this will just be remembered as a small blip in the lifetime of a title that brought players across systems together.
Update 05/26/19 11PM ET: According to a Phoenix Labs spokesperson, the game has just passed 5 million players and that it hasn't see wait times anywhere close to three hours in the past 48 hours. It looks like the indie developer is doing what it can to keep up with demand.