On the enterprise side, integrating the access and discovery layers gives a lot of advantages, especially around data governance. On the web, we give users tools to connect data sources, document them, and share/audit access to them. When a query comes through the endpoint, since we're implemented as a Postgres proxy, we can rewrite/filter/drop it in accordance with rules, or we can forward it along to the upstream data source(s) and/or join across them. If you use Splitfiles to generate versioned data, we can also provide data lineage/provenance and full reproducibility.
We've been working on this for ~3 years but are still pretty early. If anyone wants to help, we just raised a seed round and are hiring a remote team -- check my comment history for links.
[0] https://www.splitgraph.com
[1] https://www.splitgraph.com/docs/working-with-data/using-spli...