The player base was always going to decline significantly.

It doesn't have the same kind of slow grind and wide open maps with tonnes of things to interact with that kept up the populations of a game like WoW or Overwatch, so it was going to naturally decline anyway as most people got their fill of the game play and move on to the next game. Anything that is comparable either had a ton of content that was drip fed or has random loot boxes to keep people playing. This game lets you earn enough to play even the highest levels of play fairly quickly, with getting everything taking a bit longer.

The remaining population is actually pretty high for this kind of game, and it is far from dying. I play randoms when friends aren't on even though I have unlocked all the upgrades to earn myself medals, but also to help out the other players because the game does promote team play even with all the accidental team kills. I never have to wait when there are more than 1,000 players on a planet, and the there are often several planets with several thousand even when people aren't grouped up for major orders.

The community is engaged and while there will certainly be more of a decline as time passes, I wouldn't be surprised if the game gets a significant bump in player activity (old players coming back) when they introduce the next faction. Probably not double whatever population is there when it hits, but maybe 50% increase as people come to check out the new content. I think the rapid release was their original plan to keep the player base going and I'm happy they slowed down to address bugs and do quality of life improvements for a bit.

This game also has the most friendly, or at least least antagonistic, player base I have ever experienced in an online game. Although most random games don't have anyone speak up unless I do first, people help each other out, attempt to get everyone out, and there is often hugs on the ship after extraction. I have only had one player grief in dozens of random games and one match had someone who was rude. Far, far fewer negative experiences than any other game I've played.

It may get down to 3% of the highest number of players and will still be alive and kicking for those that do enjoy the game play.