It's not really doing that though. Nc+head/cut/grep are and youtube-dl is grabbing the data. Bash in this case is just orchestrating the order of communication between the tools doing the actual work, as a normal Bash script.
The post is about doing all of this in pure bash builtins like /dev/tcp and bash functions. Not about gluing together tools which do the work.
The post is about doing all of this in pure bash builtins like /dev/tcp and bash functions. Not about gluing together tools which do the work.