I'm an engineer on the Mathesar core team and I'd just like to clarify that Mathesar does support grouping to some extent. Here is a screenshot[1] that demonstrates the grouping functionality. Grouping levels are unlimited. You can play with this functionality on our live demo[2]. It's worth mentioning that Mathesar does not yet have the capability to expand and collapse groups, but that feature is planned[3].
Best of luck building Visual DB! Nice to see more innovation in this space!
Best of luck building Visual DB! Nice to see more innovation in this space!
[1]: https://mathesar.org/assets/crm-table-zoomed.png
[2]: https://demo.mathesar.org/
[3]: https://github.com/centerofci/mathesar/issues/475