It's certainly advertising, but he did seem to offer some extra role of: > wanting to point to things that work well

Which is more inline with normal HN content. Pointing to some technical thing which works well we can integrate into our coding/startups/etc.. In this case it happens to be a non-open source subscription business replacement for coding your own search, so it's very commercial, of course, but paid off the shelf solutions are technically an alternative to coding your own search with open source stuff.