I'm talking about the kind of thing you might see in a "knowledge base" or support website - not developer documentation.
As someone who grew up reading Linux documentation (such as the Arch wiki), there’s no reason why paid products should have such an unintuitive and terrible “knowledge base”.
I literally can’t think of an example.
Google Workspace has quite good docs, but not really stellar.
You can check apple support, its multi-step process where in each step they ask you a question which narrows down possible issues. I think this is foolproof for problem diagnostics.