I've been spending the last few days looking into solutions in this space for the umpteenth time and Directus does seem to be one of the most interesting ones. It's basically a non-intrusive, flexible and extensible GUI on top of your DB, plus a REST API generated from it. Another big plus is it's open source.

It actually exists since 2004, so it would be fair to say it's been more than a few years. But they recently switched from PHP to Node.

Other solutions (with varying degrees of similarity) include Strapi, PostgREST, Hasura...