I am almost sure they were invented so that people can randomly interject a conversation with "Did you know a group of X is called Y".

Exactly. It's interesting only to monolingual people or (needlessly) concerned language-learners.

"Did you know a group of sofas is called a"... just stop it. Use "group" and call it a day.

Do you know what the name for a baby cow is? It's: baby cow

and a male cow is called: a male cow

Separate words for male and female animals, and adult or infant ones, were (and are) useful for people who work with them — farmers and so on.

Indeed, but no need for everyone to care about such technical terms

Also who's farming crows?

I might be missing the point you're making, but isn't a baby cow called a calf, and a male cow called a bull? Unless castrated, in which case the bull is instead known as a steer.

What's the word for a group of baby cows? What about a group of male cows that have been castrated?

Let's use "group" and leave it at that.

Only technical people need to know such things though, in this case, farmers

You can also make them up as you go along.

A struggle of trees for a few scraggly trees clinging on to a rock way above the tree line. A knob of nudists for, well, for a group of nudists.