Earlier quoted context omitted.
Yeah. I'm not saying the jihad was the cause. But elimating AI didn't prevent the feudal system. It didn't really help, in other words. Honestly, I kinda think Herbert just didn't want to have AI or sophisticated robots in his narrative, so he contrived an elaborate reason why that tech doesn't exist.
But it did "help". Mentats had supercomputer computation capabilities; navigators folded space and charted non-collision paths; warriors had robocop like abilities. These were developed precisely because the use of thinking machines was forbidden. I don't think feudalism is going away one way or another. It persists [in various forms] because of certain biological realities, ranging from genetics to loyalty engendere…
At the level of the text, none of those things you mentioned strike me as positive developments. They just siloed computation to a biological track and those biological resources are employed by those in power, which is the same problem in a different form.
This is an aside, but feudalism is not inevitable. The vestiges of it still exist, but capitalism largely upended it.