Well yes, that's exactly my point. I've noticed that since Prince Hashem's birth in particular, there has been a shift in Rania's style. Im sure 3 kids was hard enough to manage but 4 can be a lot, especially for a hands on mom like her. I remember reading an interview of hers, soon after Hashem's birth and she candidly admitted to sometimes wondering "what did I get myself into?"
She also implied in another interview that with 4 kids she didnt have as much time to spend on her appearance, she preferred longer hair, for example, because it was easier to style, pull it up in a ponytail. I'm convinced that accounts for the shift in her style. Everyone already knows her to be one of if not the stylish and most glamorous royal around, she doesn't have anything to prove in that respect, she appears to be more secure in her role, hence the more laid back and down-to-earth outfits. There's a lot more mixing and matching in her pant and skirt suits, more recycled outfits, borrowed evening gowns etc. For those of us who are familiar with her earlier style, the change is quite apparent.