They are planning on doing something similar:

Discord is also rolling out an age inference model that analyzes metadata like the types of games a user plays, their activity on Discord, and behavioral signals like signs of working hours or the amount of time they spend on Discord.

“If we have a high confidence that they are an adult, they will not have to go through the other age verification flows,”

I'm curious to know what this "model" actually means. A real-time AI monitoring for conversations?