More info on Steam.
Destiny 2 PC is moving to Steam on October 1
Bungie's relationship with Activision, despite beautiful prospects, turned out to be not the most successful. Fortunately looks like moving to Steam should be flawless for gamers:
Hop in your ship and get ready to move. Starting on October 1, Destiny 2 on PC is heading to Steam and everything is coming with you. As the PC version of Destiny moves to its new home, we’ll be enabling you to move your current characters, gear, collections, and game purchases from Blizzard’s Battle.net to Steam. The process of linking your accounts will be begin on August 20. This will give our PC Community plenty of time to get their Guardians sorted and ready for the new launch on October 1.
Looking at this from the perspective of the current Steam situation - I mean "war" with EGS - it seems to be a good move for Valve.
Here you can watch YT announcement.