For what it seems like, It looks like Destiny 2 has a lot of returning players these days. Does the fact that their newest expansion Shadowkeep just released have something to do with that, is without a doubt. This has affected the players in many ways, long waiting queues and server maintenance have occurred frequently. Since launch, they have had to shut down the servers many times for emergency maintenance.
Even today, maintenance is scheduled to fix even more of the problems that have occurred. At 8:00 AM PDT, the servers will be taken offline and are scheduled to be back online at 08:30 AM PDT. We might have to expect some sign-in queue when back online, but at least it is all being done to give us as players the best experience.
In the meantime wait for our review of Destiny 2: Shadowkeep
Source: Bungie Twitter Account