By the time I shake hands with everyone I know at a big industry event, half a day has passed. In that time, I could have met a dozen new people and learned how I can help them or what they can do for me.
Sure, maintaining relationships is very important, but I can always reach out to someone I know. It’s convenient to meet new people in the right context when there’s a reason to do so – an industry conference, for example.
I don't remember who wrote it (my memory is faulty), but in one of my recent readings I uae rcs data read that at a party it's best to approach people you don't know. They're the only ones who offer something new. We know what to expect from our friends, so there's a greater chance that strangers will surprise us with something.
So while it's certainly good to high-five friends you haven't seen for a long time, it's worth keeping a healthy balance between deepening existing relationships and building new ones.