There are those who take the millennial reign as reported to happen by John to be literally yet fully realized.
Those who do not, just cannot claim to take the Scriptures as valid in every aspect, but look for some human rationalistic approach in which John didn’t know, Paul didn’t know, Peter didn’t know, Ezekiel, Danial and David didn’t know what they wrote was completely inaccurate, unreliable, and totally not possessing physical authority.
In the last days it is given that there are those who will understand, who it is given to understand, and all others will remain blinded.
This is why the long dead scholarship concerning the end times was hidden, and for the most of them was unrealistically portrayed, and such had to then allegories the statements, unlike now those who understand can see the realism, the validity, the honest of the ancient writers.