I have a lot of respect for the PostgreSQL team. But I think they don't care about the second part, or the constraints of the first part make it impossible. A simple example, the performance of a simple un-indexed DISTINCT on a single string column on a single table, is still quite bad for millions of rows.

Also to note, PostgreSQL has too many features for my taste. I get it's the selling point. But that usually correlates with poor performance and code complexity, too.

Of course, there's a problem of all modern fast database engines being proprietary. But by not addressing the performance problem, perhaps with an smaller engine lighter in features, open source is left biting the dust. And that's not good for the industry.