You also can't matchmake nightfall strikes or raids, they're trying something new where you as a solo player can match with a party needing an extra member (once this "feature" leaves beta) - but ultimately unless you actually know people who play the game trying to access all of the content is difficult at best.

The clan system in the game should be the cure for this, but ultimately it offers little in the way to actually communicate with your clan mates. At best you get to help level up your banner to get some perks and show a clan tag next to your name, beyond that they're useless. Every proper MMO on the planet has AT LEAST clan chat, meanwhile Destiny 2 relies on communications facilities provided by your platform and nothing more - which is a pretty big issue on the PC, since there's not exactly a way to join a group audio or chat channel on Battle.net.