Because it talks of "satan" as the 'Great dragon". That does not appear to even be the seperent in the garden. While the serpent in the garden did provide temptation, the seperent did not deceive. Adam and Eve did not die that day.
I've heard all the arguments about whether the serpent in the garden did any deceiving. They're not pertinent here. It only matters whether the writer of the Revelation believes he deceived Eve. While he does not specifically talk about the garden, it is clear both that Paul believed the serpent in the garden was a deceiver (2 Cor 11:3) and that this was the view of the churches to whom the Book of Revelation was delivered. (
Diognetus 12, [/i]Letter of Ignatius to the Trallians[/i] 10, among others)
It seems much more likely that the writer of Revelation shared the view of Paul and the churches that made Revelation part of their canon than that he shared the view of 21st century skeptics. Doesn't it?