I like the idea of the "closed" sign - so at least it's there - in your face - and you can "think about it".
That said, some would blindly ignore it anyway.
Using the ITG as the tool - I get it from the one side perspective -that's our system - and that's how we run it - it's one thing - simple and easy - and real time.
On the other end - I'm fairly young - but not a gadget or tech person - I have never downloaded any app and it's a tool I simply will not use, so hopefully someone I would be riding with does, otherwise it's an unknown to me and not something I will bother to get familiar with.