This could not be further from the truth. Different programs have interfaces that are better for certain tasks, but Houdini, Maya and Softimage XSI have all had fantastic interfaces for the most part. Software like that should be used as the benchmark other UIs are compared to. I don't know anything other software that comes close.
I wouldn’t go that far to say that they have fantastic interfaces. Tolerable? Better than what free options existed at the time? Either way, there is a lot of room for improvement but it’s also an extremely challenging environment to get interfaces right.
We are still in what is effectively the skeuomorphism for the music production industry phase (where everyone is just replicating real life tooling because that’s the expectation and with that comes a lot of unchecked baggage — except for Maya, Blender, etc it’s mostly about making assumptions based on past tooling and polishing that a tiny bit), eventually there will be a Logic to change those bad habits!
Nah. It's a problem many creative tools have (and an interesting one!). You can't squeeze one creative workflow (suitable for everyone) into a general UI.
Nah, what you are saying is vague and dismissive but doesn't hold up to the reality of fast flexible tools like these. Have you used maya, XSI, nuke and houdini?