Of course they have, the point is that Idle is not a huge problem, unless it’s important to you that your phone can idle for 5 days. This may probably be slightly less, but so what if it’s 4 days instead of 5?
How do you arrive at 4 days vs. 5? Do you have power draw numbers in idle state for the different CPUs? I wasn’t able to find much, though the manual for the ARM low-power cores suggests a lot of optimizations that aren’t available on the bigger cores.
The real problem is how much daily use you get out of your phone, and in that regard, this new SOC will beat everything currently in existence.