As someone who looks after a fairly large search engine as part of my day job I feel Danny’s pain here.
I regularly get questions along the lines of “but Google does X” and I always have to bite my lip from replying “…and Google is a multi billion pound search platform, which can afford to throw ridiculous amounts of resources and data points at the problem”.
Good search is hard, what improves search results for one user often results in another user complaining their results are now out, everything is a balance. You don’t get Google level search accuracy out of any box — OSS, SaaS or otherwise.
Unless I am mistaken Roon use ElasticSearch which is one of the most widely used search engines in the world. It’s roots are in Lucene / Solr which again are/were two of the most widely used search frameworks out there.
The issue isn’t the software, or whether it’s uses a truly open or a slightly restrictive licence, it’s that getting search results that work for everyone is hard and requires constant and ongoing tuning.
Not saying it can’t be better tuned and we’ve already seen progress there, but it’s not the underlying search engine/index software itself that is the problem.