I broadly agree with you, so I want to pick your brain a bit:

What would your ideal RDBMS / tooling look like, that facilitates 6nf effectively? Do you think it's more a limitation of the query/storage engine, or the query language (SQL), or the user interface? Do you think founding on Datalog (or similar), which kinda lends itself to "narrow" relations, instead of SQL which kinda lends itself to "wide" relations, would help here?

(I ask as one of my personal hobby-horses is trying to design better query languages and tooling, and 6nf/datalog maintains a kinda special place in my heart)