The first The Division became known for its incredible graphics, but also had a pretty unique concept for a live-service game that was really entertaining to play. With The Division 2, Massive Entertainment pretty much improved on everything and it was well received and also sold fairly well, with the series reaching over 40 million gamers in 2021. But it still sold less than Ubisoft has expected and the support has been a mixed bag.
The Division 2 was launched back in 2019, which is now four years ago, but so far we haven't heard any talks about The Division 3, and the smartphone title The Division Resurgence and the free-to-play project The Division: Heartland are the only new things confirmed happening with the franchise. Heartland is developed by Red Storm Entertainment, while Massive Entertainment is working on Avatar: Frontiers of Pandora and a yet to be revealed Star Wars title.
Now Insider Gaming reports that their sources have confirmed that there isn't a The Division 3 in development at Ubisoft, and this means we should not expect a new mainline game in the franchise for quite some time. Developing AAA-games is time consuming and takes at least three years, which means a best case scenario would be a release in 2027 if they started now (which they clearly aren't).
It seems like The Division fans will have to settle with The Division Resurgence and The Division: Heartland for the foreseeable future.