Given a choice I prefer a buddy. There are many dives I would not do without a good buddy. Diving solo does not necessarily alter the social side. Most of my diving is off a boat. Say we are diving on an easy site I know well. Perhaps my instabuddy goes through their air fast or has some other issue. I will follow them to anchor line and maybe part way up. Watch them until I know they are safely up. Or maybe send them up with another diver I know and that they agree to go up with. I then complete my dive. When I get back up we all still talk. The different groups discuss what they saw. If I note something interesting when solo I will point it out to nearby divers.