Bungie have been reportedly working on a new IP for a while now and the partnership with Chinese giant NetEase further hinted at such a possibility. They have recently trademarked Matter, which could be an indication for the new IP's name.
There is currently no indication what game genre this Matter game could prove to be, but the trademark filing specifically states it will be something video game related. Bungie didn't officially state what the nature of this Matter yet, but the key art, shown above, pretty much rules out an expansion for Destiny 2 as the art doesn't exactly match.
That is just speculation at this point though, but one thing is for certain - whatever Matter turns out to be, it will feature games as a service model or be a part of something else with that model.
This conclusion is stemming from the of the product, which clearly mentions entertainment services such as "providing video games and video game competitions via the Internet; electronic games services provided by means of the Internet or other communication network; electronic games services provided by means of the Internet...".
There is certainly a lot of emphasis on online tournaments which could hint at an aspiring eSport game, but the description itself is rather long and covers a broad variety of services, so it might even end up being Bungie's take on Garry's Mod.
Destiny 2 player base might get twitchy over this new IP though, as they have finally met the day where the game felt like a complete product with the launch of Forsaken, albeit at a steep price. If Bungie turn their attention to a new IP, they could be left hanging again, with slow updates and barely any new content.
Whatever the case turns out to be, with the fruit of being the most likely answer, there is always that promise Bungie made about plans to support Destiny for at least 10 years, if you would still believe Bungie's promises. It's not like they didn't break players' trust before.