I think Apple has been pretty clear that they are moving their ecosystem to wireless connectivity. The iPhone connects to the new MBP over wifi quite well.
And yet after the iOS10 update a lot of people had to plug the iphone in to restore it. I was also affected and was glad that I had a computer ready. I know about others who just didn't have a device close by they could use (iPad/iPhone only) and had to go to an Apple store.
Next time there will be people who had a laptop but not the adapter, because you are never supposed to need it.
That's of course just an edge case, but the fact that it just happened shows that it can be important. And Apple used to be known to always deliver a great user experience, not just in 95% of the cases.
