It is ok to ask a lot of questions, it is ok to be skeptic of friendly interactions, it is ok to be suspicious. These behaviors are not social anxiety, not psychosis, not anti-social. They are, in fact, desirable human aspects that contribute to the larger group.
There is no automated detection, no magic way of keeping these new threats away. They work by exploring humans in vulnerable states. We need kind humans that are less vulnerable to those things.