Granted. Virtual reality and augmented reality technology quickly becomes extremely cheap to buy and easy to acquire. Soon, cybernetic implants become available so that a person doesn’t even need a headset to experience virtual reality.

Within a few years, the implants are commonplace and easy to acquire all over the world. Children are implanted from a young age.

Because virtual reality provides such a strong dopamine hit, people stop trying to live their lives in the real world. Every single person starts to live fantasy worlds in virtual reality. And everyone is very happy.

The birth rate plummets, and within a couple generations no new humans are born.