My observations on the sounds:
1)The sound is more clear with headphones, but lacks punch. With my speakers, the sound has more rasp to it. I can feel it vibrate my chest at certain throttle positions. This might be harmonics kicking in giving you that pulsing feeling. I have cheap speakers, so the rasp might just be distortion even though the volume is not that loud.
2) Road going cars definitely do have gear noise. It does get louder as you go faster and the pitch does go up. However, much of the time it is drowned out by the engine, road and wind noises combined. So the gear noise should not necessarily be lessened in the cars, but the engine note and road noise should mostly overwhelm it, but it should still be there as a component of the overall sound.
3) I think the transition from low RPM to high RPM should have a steeper volume increase. I just don't think the volume of the engine gets loud enough at higher RPM. This seems to particularly be a problem with the BF1. The engine sounds about the same as before, it is just drowned out by the gear and traction control noises.
4) For any competitive driving that I have ever seen, to include club racing, as a minimum, the driver's window must be down even in road cars for safety. The only time I have seen windows up is for track days and fun drives. This would allow a lot more tire, road, and wind noise.
5) This is a sim, not a real car. I think the tire noise must be adjustable in a wider range so we can hear it over the other noises. It might be a bit of a crutch, but I think it is needed because we can't feel the g's, so to speak.
6) For those that think the cars don't sound good, try driving them like you would a normal car on the street (because that is what you are really used to hearing). Don't shift when the red light tells you to; shift into 5th like you were cruising at 70 mph down the freeway. Most of the cars sounds right. Most of us have only heard race cars from outside, or from in-car videos. Every car is going to sound different, and depending on the microphone type and location, you will get vastly different sounds every time. Don't try to judge LFS sounds by those recordings. Take elements of them, yes, but don't try to make LFS sound like those recordings.
For example, the gear noise in some recordings are totally intense. I suspect some of this is from the microphone location and is not representative of how the car would sound from the driver's seat.