Introducing separate friend groups to each other can be weird. The chemistry might not be there. Past histories might collide. However, by connecting these groups, you could also be creating a stronger social circle.
Photo by Colin and Sarah Northway
Friendships grow more difficult to maintain as they become smaller circles or individual one-on-one friendships. A larger social circle could naturally help build some momentum with more shared social events. Similarly, if you ever get into a fight with a friend or group, the rest of the circle could help mediate and mend the relationship.
Author Oliver Burkeman writes in The Guardian:
Why are densely linked friends better friends? The motives involved aren't necessarily all that virtuous. Maybe they just feel more social pressure, and worry that mutual friends will judge them if they're not nice. Even so, the effect is that in a dense network, an act of friendship is two things at once: an expression of an individual bond, and another stitch in a bigger social fabric. At the very least, it's an argument for getting over your hang-ups about introducing your friends to each other. True, they will probably gossip about you at some point, but then that strengthens the social fabric, too.
That's all a bit idealistic, and connecting friend groups may not always work out for the better. Although you may frown (or cringe) at the thought of it, introducing your friend groups to each other could also reinforce your relationships with each of these groups in the long-run.
The trouble with modern friendship [The Guardian]