They are very nice at stealing existing code and translating it to work in new place.

But the limitation is still the same: 200-300 lines code should give you something working and testable. That's not “designing an architecture”, that's “finding a place where someone's else architecture may fit”.

And yes, it's really impressive, they like to graft massive amount of code to repeat the same architecture that they found somewhere again and again.

But that's an attempt to build a skyscraper by piling twigs into a large pile. You may build a hut that way or maybe evem, evetually something similar to the ant's nest… but that's not an architecture, that's still pile of pieces not connected in any sensible order.

So Claude have duplicated something that was done thousands of times and was able to amalgamate that into something kinda-sorta-working… what's the big deal? It's very easy to see when it does that: try to ask it to add something that needs a component that is not there yet, and it would start with calling it, then trying to compile — and only then finding out it needs to be writtem. But try to do something differently from how other projects do thing, on average — and you'll discover that it would ignore your requests and would return “design” back to the average between other projects of similar nature.