I actually got the feeling at first that he was suggesting that hell is an everlasting search for reaching the perfection required on your own to be acceptable to God and, although you keep improving, you are never quite there.
It’s not where he was going, but it’s an interesting thought.
Personally, I think those that do not accept Christ, no matter how good they are, at the great white throne judgement are destroyed for all eternity. To the saved it is as though they never existed.
Re: your idea that Revelation uses symbolic language... yes, of course it does. But you seem to take that as a signal that interpreting it is now a “free-for-all”, where any theological (amateur or otherwise) may inject any meaning he wishes onto it... and that simply won’t do.
We either believe that Scripture is the inerrant Word of God, or we don’t. Too many modernist theologians use the word “interpret” as a pass-key for watering down, and for picking and choosing, whatever they like. Is the idea of eternal hell unpleasant? Well, then... *presto*! It’s “interpreted” to mean the precise opposite of what it says (i.e. non-eternal, and non-hell). Don’t like the Scriptural teachings against homosexual activity? *Poof*! They’re now “interpreted” to mean anything and everything BUT a condemnation of those practices. It’s silly, at best... and dishonest and spiritually dangerous, at worst.
As a general rule: unless there’s some concrete and immovable reason (within Scripture or within Sacred Tradition—I’ll leave aside the infallible Magisterium, for the sake of trying to prevent another rabbit-trail of a topic) why a particular passage of Scripture MUST be interpreted non-literally, then we are obligated to give the literal meaning every benefit of the doubt. Otherwise, the entire Bible becomes a farce, and every last passage can be “interpreted” away (e.g. the teaching against murder was obviously symbolic and rooted in primitive OT cultural norms, etc.).
So if the punishment for not accepting Christ is just that you die and are destroyed, is it really a "punishment" to those who don't believe in Christ anyway? When I talk to my parents about this, they are unconcerned about salvation, because in their minds, when they die, they die, and so they won't have any awareness of anything anymore.