What got my inspired here is, if a simple delay strategy can make attack harder, why not add this as a common feature in SSH? It can be called "Initial Connect

What got my inspired here is, if a simple delay strategy can make attack harder, why not add this as a common feature in SSH? It can be called "Initial Connection Delay": Once a new TCP connection is established, wait for an uncertain number of n seconds before read and respond to the handshake request.