You are right, as a demonstration there is a trade-off between using a real dataset and making the data large enough to demonstrate the performance gains. You are proving the other part of my argument though, in that you don't need to add an index (though, the comparison between using a window function in Postgres is fair, since that would be the canonical way to write that query)

As far as the "big/expensive toys", I'm using the Community Edition, which is FOSS.