Fad hole
A fad hole is when a fad goes from hot to dead, and anyone who still thinks it’s cool gets swallowed up by the hole and never comes back.
My brother still uses MySpace. He's in the fad hole and there's no getting him out.
My dad still thinks Zumba is the best thing since sliced bread. He's in the fad hole.
My cousin tried to start a Vine revolution. He's stuck in the fad hole.