Let's say that KGI was not mistaken.
The latest MacBook Air still uses the 5th generation of Intel.
By upgrading it from i5-5350U to one of the i5-8*U, Apple will double the number of cores, and more than double the performance, while keeping the same size, power, and price.
The new processors are here since September, so there is no reason for avoiding this upgrade.
On the other hand, Apple don't want to use these processors for MBP 13", because of the GPU, and prefers to wait for the next processors in the U-series of the 8th generation (like i7-8559U).
So there is a possibility that we'll have new MBA 13" soon (March 16?) with 4-cores, while MBP 13" will remain with 2-cores till WWDC at June. Or in other words, 3 months that the performance of MBA will beat the MBP's performance...
Of course, there are other possibilities too.
For example, maybe KGI was mistaken, as you wrote.
Or that the new MBPs will be released before June.