There should not be a unit that is 'the ultimate infantry counter'.
That's plain stupid.
Plus it's only 400 manpower, it's pretty damn cheap for such a unit.
Isn't that the idea behind the OKW units? They're relatively weak at the start of the game, but become exponentially stronger as the game progresses. From what I'v played, the Obersoldaten aren't expert infantry killers right away, and the only time they become a killing machine is if they have veterency and supported.
My main point is that people are calling for nerfs regarding the Obersoldaten despite the WFA just being released. There's also the fact that people are still figuring out how one are supposed to use these new units. I guarantee you that if you run an Obersoldaten unit across an open field towards the enemy, you're going to have a bad time; much like if they send just infantry to counter the Obersoldaten, you're going to get wrecked.
I'v played a few matches where my enemies(In 2v2) managed to hold back my Obersoldaten units for quite a while, so people really need to stop spreading the myth that these Obersoldaten's are reincarnations of the terminators from the Warhammer 40K universe or w/e other unrealistic comparison they can come up with.