But it's only really an subset of that demographic and i suspect the age spread reaches far lower then 18(reddit might pretend otherwise for regulatory purposes).

And i suspect a reason for the entire debacle is that a lot of the user base weren't seeing ads at all due to ad-blockers or the use of 3rd party apps.

It's a problem that also seems to plague twitch in that they simply aren't generating the revenue that's expected from the amount of traffic generated.