<h2>It was outlawed when the risk became greater than the reward</h2>

Fifteen centuries is a LOT of time for people to find and execute ways of exploiting AI driven surveillance systems.  By then they will have been used by school shooters to ID and track targets, by terrorists to assassinate world leaders using smart weapons, they will have been used to automatically steal people's identities by reading information off of things in their hands, military secrets have been leaked because someone decided to proof-read a report while waiting at a bus stop. They will have been used to automatically find behavioral patterns that suggest people are cheating on their spouses so that you can blackmail people you've never even met, there are even websites where you can just type in someone's name, and the system will start sampling video of them to generate pornographic deep fakes or sex bots of them.  As the technology becomes more prolific, the number of people with the knowledge base to exploit it grows until the harm it does is clearly more detrimental than any gain.  

As the harmfulness of surveillance increases; so to will its utility decrease.  Once a deep fake can no longer be differentiated from real footage, shady defense lawyers just need to start submitting their own versions of events to cast doubt on any video or photos submitted by prosecution and vise versa. Heck, this is so far in the future, criminals probably walk around with portable holographic projectors that can create a bubble of false narrative without ever needed to hack a single system. Together, these will lead to video and photos becoming inadmissible as evidence and therefore a useless tool for law enforcement. 

In short, public surveillance systems will become the 36th century equivalent to leaded gasoline, asbestos, or blood letting.  The tech is still an option but the very idea that anyone ever thought it was at one point a good idea seems borderline satirical.  

Video technology unto itself may not be banned since it will still have plenty of legitimate case uses, but unmanned continuous feeds probably would be.