I see. So, you didn't read what I said...
"Zom is a generic demon who is said to potentially be a universe shattering threat, comics are full of this sort of character. But since Zom does not have the prominence or proven threat level of a Surtur, Trigon, Mikaboshi or even 31st century Mordru I don't jump to conclusions about the characters chances versus any of these. As it stands I'd be wary about equating Zom to even Elders like Shuma Gorath, the King of Tears or Atum - the Demiurge... "
So basically I don't refute his power, I refute his importance. All of these Demonic types are in the same sort of bracket, all are solid universal threats, but if I did a top 20 of them Zom would not be in my top 5 frankly. And Likely not even top 10.
You will never, not ever, convince me 'Zom' is somehow more dangerous or sexy than the well established likes of Surtur, Mikaboshi, Nekron or Trigon - these have all well and truly walked the walk and talked the talk, whereas all Zom is is talk.
Hm, I'm sure somebody gets where I'm coming from with this...
Judging from what we know of ZOM in comparison to those you named his power is by far greater. When Dormammu and Umar fear you and LT is needed to cast you out I tend to believe he is a greater threat if unleashed than the likes of Surtur and the others. I get your point being those you named have done alot more over the course of time but when ZOM shows up it takes the Heaviest of hitters in the cosmic landscape to rid the universe of him.