Interesting to see this quantified. Clean structure seems to lower the cognitive load for both humans and agents, which probably explains why naming and modularization matter more than we think.
The way we should define code quality is arguably how easy it is to affect correct changes to the code, that's hard to quantify, but ultimately the thing any code quality metric is trying to capture.
Based on that, it should be a pretty unsurprising conclusion as long as the code quality metrics you are using are reasonable; as long as the quality metric is good (within the context of coding agents), then this is the result we'd expect to see.
The way we should define code quality is arguably how easy it is to affect correct changes to the code, that's hard to quantify, but ultimately the thing any code quality metric is trying to capture.
Based on that, it should be a pretty unsurprising conclusion as long as the code quality metrics you are using are reasonable; as long as the quality metric is good (within the context of coding agents), then this is the result we'd expect to see.