[threeseed]

> For example, putting the same dataset in Postgres or ES wouldn't make one deliver more relevant results given equal configurations.

This is not the case.

The OOTB search capabilities in ElasticSearch (even by default) far, far exceed what you get in PostgreSQL FTS.

Also you're completely contradicting yourself. You say you don't advocate reimplmenting something provided by the tool but then suggest doing exactly that.

[pauloxnet]

But in many situation you don't need all the ES features and you can implement a quite good and fast FTS function directly with your PostgreSQL database if you already use it in your stack.