For threat intelligence investigators, sophistication has stopped being a reliable signal of who is behind an operation.
From Ben Buchanan, "The Legend of Sophistication," "sophistication bears on the applicability and utility of the offense-defense balance in cyber operations, an area of both academic and policy debate." "Sophistication" is often an ill-defined term. I think in this case, "technically clever" would probably provide a better definition.
The cybersecurity skills of AI models means that AI has collapsed the labor and tooling gap that used to separate well-resourced, state-sponsored operations from individual operators.
In terms of tooling gap, there is some variability. While state-sponsored adversaries are generally better resourced, I would argue that some groups like "Salt Typhoon" and "Volt Typhoon" are very adept at living-off-the-land. And numerous other APTs are likely using open source and security tooling to great effect, so I would argue that their knowledge of how to utilize those tools has made them much more effective. And that, is where the gap is truly closing. Where an AI model can potentially walk you through an attack chain