I clicked the "enter" button without selecting a year and the URL changed to https://www.j-14.com/?age_gate%5Bbirth_year%5D=&age_gate%5Bc...
I would assume the better way to notify users is the way other sites have an alert bar at the top or bottom with their cookie policy.
https://guardianproject.github.io/haven/
https://www.nano-editor.org/
https://www.humblebundle.com/books/artificial-intelligence-b...
Certainly seems like anticompetitive behavior.
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