I think the idea of "software architecture" may become irrelevant.
Architecture, in the sense of applying/enforcing organising principles like modularity and levels of abstraction, is something we currently do largely to manage complexity -- so that we can fit as much of the system into our limited brains as we can. For a large enough system, this is necessary in order to work on it efficiently. But if you can "keep the whole thing in your head" without using these "crutches", then there's actually no need for them. They become overhead that can be done away with. We do this already for sufficiently small things -- no one plans a software architecture for a "Hello world" script.
It's possible that future (maybe even current?) AIs will be able to "keep the whole codebase in their heads" just fine, in which case the need for architecture goes away.
Architecture, in the sense of applying/enforcing organising principles like modularity and levels of abstraction, is something we currently do largely to manage complexity -- so that we can fit as much of the system into our limited brains as we can. For a large enough system, this is necessary in order to work on it efficiently. But if you can "keep the whole thing in your head" without using these "crutches", then there's actually no need for them. They become overhead that can be done away with. We do this already for sufficiently small things -- no one plans a software architecture for a "Hello world" script.
It's possible that future (maybe even current?) AIs will be able to "keep the whole codebase in their heads" just fine, in which case the need for architecture goes away.