@chpietsch yes, I guess you could look at it as naive. In many ways robots.txt was naive too. But one aspect to this is that we need ways for rights holders to assert their wishes, so that courts in jurisdictions that care (e.g. the EU) can use them as evidence. And there needs to be more nuance than what robots.txt provides:
https://mailarchive.ietf.org/arch/msg/ai-control/EJ-84k8Zzh21vY1dHPZvDeYOLes/