Revelation 20 is not symbolic of anything. Revelation 20 contains the literal actual events. Revelation 20 does not need an explanation.
The explanation by the angel is still unclear and obscure. Daniel was not meant to be understood, until years after the facts have already happened. Jesus said let the reader understand. Not the reader of Daniel. The reader of the historical account that has already happened. No one in the NT ever said Daniel is being fulfilled, nor has been fulfilled. It is 2000 years later, and we see the historical record as having fulfilled Daniel. Yet some claim Daniel is still future. How would you know, unless God tells us at that final judgment, what was fulfilled, and when.
Everyone states the 4th beast was Rome. We know from history that Rome was no longer in existence after the 5th century, in any way or form. All of Daniel 7 has been fulfilled including the coming of Jesus and the Cross. Did those living in the first century have a clearer understanding than we do? I don't think so. A lot of church fathers did not recognize that Jesus had fulfilled Daniel 7. So many here carry on that tradition, and claim Daniel 7 is still left unfulfilled until the Second Coming of Jesus.
That is not a Preterists position to say Daniel has all been fulfilled. That is just from understanding the historical record. What is Preterist, is saying Revelation is the same prophecy as Daniel, and Revelation has also been fulfilled.
We have seen the rebirth of Israel, and nations rise against nations. We have seen OT prophecy fulfilled. Yet many will argue the OT is either too obscure, or their interpretation has not been carried out as they see fit.
I disagree that revelation 20 should be taken as 100 percent literal.