The cost of engaging with the miserable: Were we always this lonely and embittered?

I think he's got a point but misses one key thing with his main question:

Misery, famously, loves company—and, however shallow, social media provides that in droves. It’s worth asking: What if the internet so frequently feels miserable, and makes those of us posting and reacting feel miserable, because so many people are miserable in the first place? What if we all absorb that misery at scale online and, sometimes unwittingly, inflict it on one another?

Like, we are all miserable at various points in our lives and one of the notable aspects of feeling despondent is that you both crave connection to other people but also feel overwhelmed by the prospect of having to do all the planning and emotional regulation you need to schedule and maintain a connection. For some people the balance tilts towards making them retreat inward, ignore that drive for connection, do something to recharge, and come back when they have that social energy again. For other people the balance tilts towards making them get over the hump, engage in some sort of social activity, and recharge that way.

In either case our intuitions are probably mostly right. If the prospect of socializing seems too much it's probably right to stay in and if the desire for connection is strong enough it's probably for the best for us to seek it out. But with social media you kind of have a simulacra of social connection with minimal cost at your fingertips. So you can sort of try to achieve that social connection without having to do the same amount of work with emotional regulation to get it. The key thing, though, is that you're not in a good mood and probably shouldn't be engaging with people. I realize that one of the reasons I retreat inward when depressed is because I don't feel like having to perform social niceties with people I don't know well. All that stuff is kind of tiring, but if you get the emotional distance of only tweeting at people you don't really need to do it. But those things are still important! When you don't do those things you end up looking and sounding like a bit of jerk! And, consequently, we all end up acting like jerks more often than we'd like.