There was over a million people playing at launch and this sums up the experience perfectly (this was posted around a week after launch):
So even if people come back for ladder, if its the same as above, it’s still a lackluster experience compared to the original game with the same population.
PD2 does combine everyone in 1 game-list, but there are more hardcore games up with 1300 people than what we currently have, and that’s only because of the way this online mode is set-up.
I even turned on a VPN and connected to different parts of US-East, I got a different Hardcore list each time, so I can confirm that it’s not a lack of players that is the issue here.