Via Icecast, you can simply check the box “Count listeners” in the encoder settings (Select encoder → Configure) and the update time in seconds is displayed to the right of it.
I don’t think it will work via YouTube, as you have described here.
Don’t get me wrong, but I hope that mAirList will never work with something like AI.
I am very happy with this program that has been developed by an intelligent PhD in Computer Science together with a community of human radio enthusiasts over many years.
Since I’m not a fan of AI in our normal life (I can’t see any progress in it), I would not recommend AI algorithms in the mAirList code.