But whereas Nero just killed Christians and his perceived enemies outright with beheadings ..., Domitian was famous for sending them into exile. Thus John instead of being beheaded was exiled to Patmos --- a fate that would not have been given to him by Nero, but would have been and was given to him by the one who followed in Nero's footsteps.
That may be true but there is no written historical records abscribing such a thing; it's pure conjecture. I would argue that it would be just the opposite. Saying Domitain was referred to as Nero would be similar to an argument 2000 years from now of saying Stalin was really Lenin or Hitler was Musolini. Historians, especially in the very ancient days, would not have called different people by the same names. It would be too confusing.
This is rather significant in my mind because there is far more evidences of Revelation being written prior to 70AD than in the 90s. The 70s group is pointing to the Syrian text (states John was sent to Patmos by Nero), Jerome's writings (states that Nero tried to kill John at the same time of Peter and Paul) and the Muratorian Canon (which states Paul's writings were based upon John's writings).
The 90s group is pointing to one statement made by Iraeneus a hundred years after the fact and quotes from other fathers pointing to what Iraeneus stated. They refute part of the Syrian writings by saying that Nero isn't really Nero at all but Domitian, although they offer not historical proof for this claim.
Now, honestly and objectively, what do you think sounds more credible?