That makes sense and I (native English speaker) had always assumed it was something like that.
I wish people would present this as what it is (a childish word game) rather than legitimately “part of English”, so that learners of English don’t think they have to memorize these and actually use them…
Some of them are, some not as much. There are certainly more obvious poetic devices like a "murder of crows" yet there are still many other collective nouns that are more "legitimately" part of English - pack, herd, pod, flock, swarm, and school for example. You don't have to know these terms as using 'group' would be understood - but they are common enough in books / documentaries.
I wish people would present this as what it is (a childish word game) rather than legitimately “part of English”, so that learners of English don’t think they have to memorize these and actually use them…