As far as I'm aware, that's normal with NGP cars, regardless of the version (note that RSRBR uses an old version of NGP).
Generally speaking, WITH AUTOMATIC CLUTCH, you have two types of NGP cars:
1) what you just described (most common in WRC cars, I think). It is what it is. You can actually drive through stages without a single push of throttle.
OR
2) for the sake of example, let's say you've spun and there you are at a standstill facing a wrong direction and feeling like a ruddy eejit, you put on the 1st gear -> push throttle -> nothing happens, no revs at all. The revs can only go up on neutral. Which is just a pain if you're on very narrow road and you have to do some extra manouevering with reverse and 1st to get going in the right direction again.
That 2nd scenario is understandable as a design, I guess (to make things harder for those without a clutch), even if it is still different from not only the original RBR physics but all the other games I know when using an automatic clutch.
Or it may be just porridge talking trash again. Let the arguing begin.