It used to be that you could try to do content, ask to join a public party, and likely be put into one. If there wasn't one available, start your own and you'll probably have company soon enough. On Saturday, I did a tier 3 run at the highest difficulty level. There were no parties available to join, so I started my own. I did get another player to join for about 2 1/2 depths, but then he left and I was solo the rest of the way.
So I thought, maybe the people are in missions. That was the big thing in early 2012. Well, between yesterday and today, I've cleared all of the 10-1 missions. In all three cases, I tried to join a party and none were available. I started my own public party that others could join, and none did, so I was left to solo.
So what happened? Is this game dead now? Am I selecting the wrong options so as to accidentally disable partying with others? Has scattering players among the arcade, various missions, and three difficulty levels diluted the player base to the degree that there are too many boxes and not enough balls fill them?
/burps