Initially it was a combination of just for the fun of it (it's a small script, as OP described). Secondarily there was the feeling of "everyone is going to go work at [major competitor]" and I was curious whether I could collect the data to show it. (I never ended up looking into this, but maybe HR did.)

As a dumb script it was not designed to be especially flexible. One thing I remember needing to fix was that by its nature it was archiving old data and preserving it, which meant that it was accidentally deadnaming trans people. My recollection is this was a small code fix, but an interesting lesson in social consequences of oblivious software.