I don’t really think l this is necessary. I haven’t really looked into it too much, but if there is already a function that the Tower uses to tell to go around, 360, or something like that like you say there is, then you should just do it. Does a differently labeled airport really have a different affect than ATC telling you to do something? Also often times ATC tells me to go around when I am literally like 2 seconds from touching down. I do it anyway, because in real life it is what you do.
You’re right, the Tower ATC does have instructions to regulate or deny inbounds.
The idea of the feature I am proposing is that Pilots see from far that the airport that they have selected as their destination is not accepting inbounds. They can then alter their flight plan and choose another airport.
360’s and go-arounds are very different to this. This is a preventive measures, not a reactive measure
Today this topic came up again, on Expert. With limited airports open, airports sometimes just get to much traffic.
The idea I present here allows pre-warning to pilots to plan a route elsewhere, so it doesn’t get confronted with a ‘this airport is not accepting incoming traffic’, at the end of a flight.
Obviously it can work the same way for pilots who plan to spawn at an airport which already has an over-full platform.
In short: vote!