The real problem is not with programs flooding the terminal, but rather that if the foreground program isn't accepting input (perfectly normal for many programs

The real problem is not with programs flooding the terminal, but rather that if the foreground program isn't accepting input (perfectly normal for many programs) then by design the socket buffer will fill up, TCP flow control will kick in, and the client machine will stop even sending the bytes to the server. In order for a ctrl+C to get around the backed up buffer, it has to bypass the regular queue.