And the reason is simple:
His summoned adds interfere from other players to reach and hit the boss. There are too many of them, and they have the habit of crowding around a boss.
Regardless of how cool Doom is, he is more of an annoyance to other players because of that specific issue. Especially melee heroes.
I hope other people will follow as well (and I'm sorry Doom lovers), until the outcry is big enough for gaz to finally fix this.
Again, this is not a hate crime against doom players and lovers. This is about being interference with others.
That is all.
Thank you for listening.