I disagree:
The phrase 'tight-knit community' exists, and is fairly commonly used.
A 'loose-knit community' would have... less direct ties, less overlapping ties between everyone to everyone, would be more... islands of people connected by a few inter-island connections... maybe less frequent interactions between members...
A social network is often mathematically/academically/professional ly described as a bunch of points, clustered, with connections between them.
Even the very word 'network' is etymylogically derived from a net, an interwoven mesh.
You very much can literally loosen or tighten a net, make one that is more pourous or more dense in terms of threads in any given surface area.
Hey there ya go, even Threads is an actual name for a social network.
I think the metaphor or analogy of social networks being described by other terms that literally apply to an actual net or fabric is... actually incredibly common.
... You've never heard a person being described as having 'loose ties to (other person/group)?
Have you never watched any kind of detective show, a 'stop the terrorists' political action thriller?