You can't forget that the only places we do find security camera's are places that survived.
Now which pre-war places had survived? Vaults and bases (ie military/underground facilities) So that makes sense those high risk places would have any from of security.
But, what do we see mostly out in the wastelands? Broken down buildings. Buildings that previously held businesses, homes, facilities, ect. At the very least if security camera's were available before The Great War, a large majority of the rich would have had them if they were caught in the sensationalism. Which also means very wealthy businesses would have them, hence Vault-Tec employing them in their structures. This clearly means cameras where available to the public, well those who had the money.
Also The Enclave, is the reminisce of the US government, they have the know how to build robots and maintain them as one can see with K-9 built by the scientist at Navarro.
What i'm trying to argue here is that the reason for such rarity of the security cameras/robots is because over time without maintenance these robotic structures would either break down or became victim of the post war disaster and thereafter. The only places we do see robots/security cameras are places that were either protected like Vault City or left untouched due to the place being inaccessible like Mariposa Military Base where they had at least maintenance on any existing robots/security cameras. Which extended their life for so long.
Whether or not to implement robots/security cameras is up to the developers, i was simply trying to state the fact that its robotic structures are rare because most were destroyed and the only surviving ones we see now are places that survived. Not because the knowledge is lost.