Seems like it would be harder to become friends with coworkers, or easy feel isolated in your work (particularly outside of software development).
On the calls we talk about random stuff like our hobbies, what's going on in our lives, what we did this week. Occasionally we talk a bit about work but we usually try to keep it as socially focused as possible.
I've found that it contrasts well with the typical situation of being in an office. In office I find there is continuous social interaction, but it can be more shallow (banter, quick chat, etc), whereas a 1:1 format like this allows you to develop a deeper connection with each person and have more nuanced discussions.
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