Advanced fabbers build all advanced factories

So often when i play the game, i usually focus on bots or tanks.
However when i want to build a more diverse army later on my army of example tank fabbers need to build a t1 bot fact built a bot fabber and only then can build an advanced bot factory. Same with Air.
This is actually quite annoying and i don't see the benefit of this.
I completly agree that the low tier fabbers should only be able to build there corresponding advanced factory but i think advanced fabbers should be able to build all advanced factories.
What do you guys think?

moved to balance discussion section

i don´t realy care but i don´t think this change is neccesary ...