AI-generated personas in online communities - detection or lost cause

Been thinking about this a lot after reading about that University of Zurich study where researchers ran AI personas on r/changemyview without telling anyone. Some of those personas were posing as trauma survivors and abuse victims to influence real discussions. The fact that it got that far before anyone caught it is kind of unsettling. And that's a research team with presumably some ethical guardrails - imagine what a motivated bad actor could do at scale with current models. The detection side feels like it's always playing catch-up.