Back when I was the Super Hornet Model Manager, I worked with the FAA to see about getting the centerline thrust restriction changed. The ball was already rolling by the time I got to it, but the FAA memo removing the F/A-18E/F was sitting on some big wig’s desk waiting to be approved, or so I was told by Oklahoma City. At the time the FAA was way more concerned with UAS, and they were still overworked and undermanned, so it wasn’t a high priority. Here we are a few years later and it’s barely hitting the streets.
As for why the Super Hornet was on FAA 8900.1, and the Grower is not - both flight manuals are virtually identical and have the exact same language in them. The biggest difference is some minor formatting items and the actual differences between aircraft, which are few. The Super was seen by the FAA as a new variant of the legacy Hornet, which was already on the list (just a continuation of the F/A-18 series). When the Growler came out, it was a labeled as a different model (think T/M/S, F/A-18 vs EA-18), and it had its own flight manual with the proper language already in it, so the community was able to successfully lobby the FAA to either keep the jet off the list, or to have it removed very quickly.
We now return to our regularly scheduled programming....