The trick to get around this is to move smoothly up and down the gradient of social interaction intensity, never dropping below a basic floor of presence: the sense that there are other people in the same place as you.
Instead of having two modes, “in a call” and “on my own,” we need to think about multiple ways of being together which, minimally, could be:
In a video call
In an anteroom to a video call, hearing the sound of others
In a doc together
On my desktop but with the sense that colleagues are around
And the job of the designer is to ensure that their software ensures the existence of these different contexts, instead of having the binary on-a-call/not-on-a-call, and to design the transitions between them.
When we use non-spatial social apps, we often understand that another's cognitive presence is there, but we can't feel the more human presence we're wired to need. When we're not social distancing, we fulfill this need elsewhere, outside of software. We meet for coffee. We go on a walk. We play a game, or show a friend something funny on our phone and watch them laugh. We have infinite options at our disposal for relating to others. Though the lack of these same options inside the software we use is sometimes inconvenient, we can usually get over it.
But things are different right now. We're constrained to rely almost exclusively on software for social interaction. What are usually minor inconveniences in our existing applications are now the main factor preventing us from fulfilling our social needs.