Let me say this... In my opinion, Disney declines to issue fastpasses to new attractions because they know that FP artificially increases wait times and since the demand will be at it's highest at a new opening they know that people will move along smoothly and with far less stress without FP. It doesn't take a Rocket Scientist to figure out that if it helps enjoyment, overall, to guest for a new venue, then it will be even better for the less popular attractions throughout the parks.
Fastpass was something that looked good on paper (either paper pass or FP+), but, just didn't do what was expected. It managed to make a few that were willing to spend hours online or on the phone to secure a few precious passes the ability to get on quicker with FP, but, you have to plan your day around them and since it still is limited as to how many you can get, the fact is that if you want to do any of the other attractions you will be stuck in a standby line someplace, feeling frustrated as others legally cut in front of you, the one that has been standing in that line for what seems like days. It creates anger, frustration and stress, none of these things are what are usually associated with a fun vacation experience. As a person the goes back to pre-FP day and experienced every incarnation, the experience was a whole lot more fun before the FP era's I don't mind telling people that it was so much better before. Anytime that anyone has to feel anger and frustration in what is supposed to be a fun experience should be able to easily see the flaw in this system.