The Division 2 is best experienced when you play in groups. Ideally, with 3 other teammates, but you can also do well in a group of 2 or 3.
Progression is easier and faster. Nothing takes down a boss more efficiently than a group of agents focusfiring their Specialization weapons at once.
If you find the silence in the Dark Zone a bit oppressive, you'd better get yourself a nice teammate who can either: entertain you, revive you or stab you in the back if you choose your friends poorly.
Join a Clan to find regular teamates who share common interests and playstyles.