I've read of this new term called "Layer-3" or L3 for short. It's basicially a network built on top of a Layer-2 network which also relies on a Layer-1 network for security. If L2s are supposedly enough for scaling, why bother making networks on top of them? It doesn't make any sense. Unless L2s have the same limitations as L1s and developers need to create L3 networks to keep fees low and speeds fast.
These layers function differently.Layer 1 primarily functions to ensure the security of the blockchain. Layer 2 is for scalability while Layer 3 is to host applications that could be used for different kinds of utilities. Since these layers function differently, they also solve different kinds of problems.
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Do you think L3 networks are necessary? If not, why? Do you think they're overhyped? Your input would be greatly appreciated. Thanks. 
Layer 3 is implemented to further improve a blockchain. Much lower fees and much faster transactions. I think there’s nothing wrong to add them especially they can make a blockchain more efficient.