I put that in quotes because at those scales the sub-factory for creating a single input resource might be bigger than a whole base used for launching a rocket. That's why most of the factories you see north of 2k SPM aren't main bus designs (aka well organized monolith), they're modular designs ('microservice' based). If you're going for one of those crazy ridiculous high output post-endgame factories, the sheer complexity of running 8+ belts of one resource and branching off 2-3 belts at a time, then having to double that to go from 1k SPM to 2k SPM is way too painful. Main bus designs work really well for building one factory to launch a rocket because the resource demands aren't so high that you run into belt scaling problems. The 20+:1 compression ratio you get from moving blue circuits offsite is a much bigger win. In practice demand for green circuits is so huge primarily because of demand for blue circuits, so I will often make all circuits offsite and ship them in.

Most of the other resources for which you consider centralizing production, you do it because you save a ton of bandwidth by centralizing, or because demand is always high, or because the inputs are more complex to move (such as fluids). Green circuits are distinct because (1) they don't save that much space compared to the basic materials you input to make them, and (2) demand for them is modest at first, but becomes a primary bottleneck if you're going for scale, and (3) their inputs are resources you need almost everywhere, so they're already there anyway. Additionally, the production ratios (number of assembler units you use for each intermediate product) will change, so it's easier if all of the green circuit production is in one place than to make individual changes in a lot of places. At that point the plumbing itself becomes so complex to maintain high throughput that centralizing green circuits is an economy of scale decision. However, if you are trying to do a megabase (where you keep playing post-endgame and basically scale for the sake of scale), your green circuit demand shoots through the roof, and you will end up sinking half of your basic materials into making green circuits. And they only require the two basic input resources that are needed almost everywhere, so the alternative of making them on site isn't that complex either. Many of the production chains that take green circuits as an input require such low quantities that 1-2 assemblers is more than enough, so the marginal complexity of trickling them to where they're needed is low.

Electronic circuits are a great example of 'it doesn't really matter because for 99% of players the factory won't fall apart due to this decision.'

Factorio demo multiplayer