I'll miss the ugly little bastards, but for the unaware I think it's a good change based on what they say in the article.
Hear me out. Deer, elk, and the like are generally passive huntables in every other survival-type game. I reckon a lot of people coming in used to those games are going to see one at a distance and think "Oh, a deer! I can use some venison, my character's a bit peckish." only to realize the thing is a fucking tank that can melt your brain and call other mutants into the fight. It's a trope-flip and I think it could work great. It reinforces the central idea that everything in the zone is hostile, dangerous, and not to be taken lightly.
Tushkano rats are a great example of this from the original games. Most RPG games put rats as a bottom tier enemy, the first things you encounter and kill in some old ladies basement. I think we all can remember at least one point jumping onto a truck hood, after getting swarmed by a group of them and getting your armor/health absolutely shredded. They look like malformed hamsters and can be dropped with a single round of buckshot, but they spawn in packs and those packs will fuck your shit up if you're not prepared for it. I can see psy-deer working similarly.
