Well, the answer of the first question makes it obvious that they are wasting the efforts in the wrong way. I really haven't played any of the Forza games, other than a couple of laps in Forza 3, and the sounds there were incredibly well done. They were accurate, not "13-year-old-kid loud" or compressed and artificial as other games. The most important thing was that all the cars I tested had the right sound sample according to the engine type; something that PD fails miserably in some cases. If good sounds were achieved in an old gen game, then saying that hardware limitations are the problem is no excuse.
The lack of common sense in whoever chooses which sound goes to what car in PD sometimes makes me want to hit my head in a wall. It really isn't that difficult. Yes, YOU! Whoever you are! You wouldn't know the difference between a V10 and a V12 even if you put the engines apart and count the pistons yourself! You know nothing about cars! You shouldn't be working in that company! Since GT2 (GT3 really, since it's the second GT with "accurate" engine sounds) I've been waiting for these inconsistencies to be fixed, god dammit!! Enough is enough.
Sorry for the rant.