Originally Posted by
chevvron
Irrespective of whether you have Mode S, the controller still has to observe an ident squawk on their radar in response to a request to the pilot; it's the law.
That's incorrect, unless I've missed an SI at some point to withdraw the Mode S identification criteria...
In my view, the reason why the majority of controllers don't use Mode S identification is the old "we've always done it that way here" reason.
Another possibility, as mentioned above, is that the ground equipment is not suitable for it. Which, if that's the case, is rather disappointing in 2021.