Reading between the lines and this is the first I am seeing of this like everyone else.
I think this is a way of cleaning up the various systems of keys and airplanes, which is a good thing and is also as a result of them adding the contracts item too.
My perception is that everything Gold Plane related will remain the same, but almost certainly silver planes are likely to be a higher amount needed. This is similar to many other games. Pay money get stuff faster. So for example and this is hypothetical. An A380 may cost 28 Gold Planes to unlock, but could be 40 Silver. Or they may leave it the same due to the time taken to earn so many Silver Planes.
I like the simplicity of it. So I am curious how they are going to manage it, but as I said, given the contracts piece and the reputation piece it looks like it’s coming with it. A necessary change