I guess this is really two news pieces in one. The first bit of news is that apparently Natural Selection 2 (opens in new tab) has been getting updates for the last 11 years, ever since it was released at the tail-end of 2012. The second bit is about how that's all over now: Unknown Worlds Entertainment has "ceased active development" on the game as of yesterday.
Well, kind of, anyway. The truth is that Unknown Worlds handed over development (opens in new tab) to the Natural Selection 2 community as long ago as 2014, and—as far as I know—most if not all of the patches since have been created by dedicated players rather than Unknown Worlds staff. I'm not sure if the end of active development on the game comes at the behest of Unknown Worlds or the community dev team, but I've reached out to the studio to find out and will update if I hear back.
The statement announcing the end of development makes it sound like this is a move by Unknown Worlds, though. "10 years since its official release and over 117 updates later," the studio says it's sending Natural Selection 2 into retirement so that it can focus attention on other projects. With games like Subnautica and Moonbreaker (opens in new tab) to take care of, it makes sense that the company wouldn't want to dedicate work hours to tending a decade-old, team-based FPS, even if most of the work was being done by fans.
The community reaction to the announcement has actually been mostly positive, with several fans expressing astonishment at the game lasting this long and thanking the studio for keeping it going. The top-rated comment on the announcement on the NS2 subreddit, from a user called totalnewbie (opens in new tab), just says "The fact that they kept working on it for this long, and still support it [...] after all these years for what is a very small community, has been amazing". Another, from askLing (opens in new tab), says "Huge props [to] the NS2 team for keeping it going for so long! Dozens of AAA multiplayer shooters have come and gone in NS2's lifetime."
We had a great time with the game back in the ancient days of 2012. Craig Pearson scored it a resounding 90% in his Natural Selection 2 review (opens in new tab), praising it as a "wonderful one-off" whose RTS elements served to tie the thing together into an excellent and cohesive whole.
So it seems that Natural Selection is coming to a natural end, and everyone seems pretty ready to live with that. But if the news has you hankering for one more session, Unknown Worlds says it "will still continue to host matched play servers so that community members will be able to play games on-demand with other players or bots". I'd get in there fast, if I were you.