The problem is only the A380, because I just checked now, and we have several gates large enough for 777/747, with a radius larger of 33+ meters:
E32, E26, E20, E33, E43, E49, E57, E67
If you checked the radius on GSX, it might be different because that's only used to drive the default vehicle starting position ( if it's not further customized ), but AI won't use that, what counts is the size in the airport .BGL which are surely enough for B747/B777, but I see we should add the ones for A380, which I think are only a couple.