Dear,
The AGE VERIFY pop-up appears only few seconds AFTER the complete loading of the page. Between this time, there is like 1 or 2 seconds in which the user can naviguate and scroll down the page.
As the user scrolls, the age verify pop-up won’t appear to the user. The page will grey out but the pop-up is only up in the screen. You may answer me that this is not a real user scenario, but YES it is. Nowadays, all users want a website loading very fast where they can scroll very fast, so it’s a REAL case.
Solution? The pop-up should be a layer/level up, meaning that the pop-up should appear fixed on the screen (no matter if the user has scrolled or not).