It's more "what one tool can do everything", not that its ideal. Like why people use Microsoft Teams even though its terrible.

The relational model and sql force us to simplify our data models too much by eliminating relationships or just not dealing with them.

Think about a nested json blob from some web service api and storing it in SQL in normalized tables. No one is going to do that. Everything just becomes a denormalized mess and everything is hacked around it.

Instead of modeling things in the proper way, most of the world's data is modeled in a way so that we don't have join explosions in sql queries because they look scary. Data pipelines become these scary batch transformations where data is dumped somewhere else without anyway to trace back where it came from.

I encounter so many end-user applications and systems where you wonder: "why couldn't they allow a list of items here instead of a single box" or "why can't this reference this other thing".