Robert. I am amil and most of my friends on this forum are amil. In many cases we have come out of pre-mil backgrounds, and feel strongly (vehement is the wrong word) because we feel a sense of having been deceived about it earlier in our Christian walk. When I was first saved we were fed a continuous diet of late great planets, Tim LaHaye, alignment of planets, Y2K bugs, blood moons, rebuilt temples, economic collapse and pending doom.
When we found traditional eschatology, some got relieved, others got excited, and others got just plain angry.

Surprise? I can only speak for myself. I don’t talk much about the millennium question except to say that I prefer the term ‘realised millennium’ rather than ‘amillennialism.’
I dont do “vehement.” But I support my friends with a bit of encouragement because they have made it there business to expose what has been bad eschatology and bad fruit for too long. I hope that answers your question bro.
It does to a degree. Thanks. I know for myself what it is to have believed false doctrine, only to find out it was tradition of men. However, there's a real difference between having been taught licentious liberty, or carnal Pentecostal holiness, than pre, post, or amillennialism.
I am actually post and pre millennial: We are now Spiritually raised with Christ, and one day with the Lord is a thousand years, and after a thousand years with the Lord, it will still be as fresh, lively, and good as day one.
However, that does not mean we have the right to throw away literal prophecy, just because we experience the spiritual fulfillment of it.
Ex: Just because we understand the spiritual significance of crossing the Red Sea on dry ground, as pertaining to our salvation and sanctification in Christ, doesn't mean we now dismiss the literal fact that it happened with the children of Israel.
Many people do that very thing, and I say it is no different with the millennial reign of Christ.
However, so long as we are spiritually resurrected with the Lord to sit in heavenly places now, why get all hot and bothered about differing interpretations on the millennium of Revelation?
I think it's mostly knowledge pride and heated arguments about pet doctrines. Afterall, a whole lot of study can go into that stuff.
I find that many sicere Christians have put so much time and effort and perhaps money into discerning certain doctrines, as well as a measure of revelation, that pride gets in the way of allowing any correction, whether great or small.
No matter how learned we get, we must never cease to come to Jesus' words, and the teaching of others, as little children without preset agendas and conclusions.