I have found that if you give it a pre-baked architecture to work within it works really well. It's not really what you'd use here, but just saying "this project uses a ports and adapters architecture" can stop it from generating mush by default. I think it's not so much that they're bad at it as that they don't have a clear reason to pick something other than mush. And not just "something" - a specific something, from a fairly short list of architectures suitable for your problem domain.

Yes, totally,with examples and references.

But there's something existential there maybe?

NASA says, any time you make a program that has a new 'launch vehicle' (aka architecture) - the whole project is the 'launch vehicle'.

'Oh, you want use a new architecture? Welcome to the cesspit of hallucination!'

Basically, there's a lot more complexity than we might imagine 'hidden in the nothingness' of he unknown.

Pick a 'known off-the-shelf launch vehicle' first ... then you design the landing craft