I don't think the contention was that the feature or ability doesn't exist, but rather that companies choose not to do it. When you worked on those systems - did you set up anti-passbacks?
Yes, it was in France and related to security, we had to ensure that the area antipass back was working properly, there were several areas where "random" entry was highly prohibited (let's say live shows).
Recently I worked for a bank where they had different types of entry airlocks, it was a bit a pain, especially the multiperson ones.
