MFI certification I don’t. They didn’t do it with iPads or MacBooks, why with iPhones?
Kinda already answering your own question. Those products converted to USB C a while ago, and there hasn’t been a technical reason to not convert iPhone for at least as long. Why not iPhone? It’s probably because if I had to guess, the MFI business is like, a lot of money. Probably hundreds of millions.
If you follow apple and the rumors fairly closely, this is one that at this point will be a surprise if it doesn’t happen.
Just thinking about this point for a second is really mind-blowing especially when you think about it with the added context that up until about 200-300 years ago, human technology levels were probably closer to the stone-tool wielders than it is to modern humans in an EV listening to music through a smartphone and navigating by a global satellite system.