I've been observing this thread and not commenting because a lot of this is just opinions and the typical Android vs iOS nonsense. With that said, I cant see how anyone can say Car Play is better than Android Auto. They are worlds apart IMO. Android Auto, especially with the new UI that released recently, is so far ahead of Car Play its almost hard to compare them. Android Auto is more aesthetically pleasing, more important information is available, its easier to switch between the apps you use the most, and most of all Google Assistant is SO much better than Siri. For a software thats built around being hands off, the assistants ability is important and again its not even close between the two.
With regards to the whole iPhone hardware falling behind...agree and disagree. When it comes down to hardware only, iphones are still better than 99% of the other devices available. The only ones that really beat them are Samsung which are squarely the leaders in that department. And Im not talking about processing and RAM because iOS is more efficient with RAM so packing 12 GB of RAM in a phone doesnt mean anything because its not an apples to apples (no pun intended) comparison. And when it comes to build quality, its Samsung and Apple and then a big drop off to everyone else. However, if you look at things like display quality, form factor, weight, storage speed, charging speed, and battery life I thinks its pretty fair to say Apple have fallen behind in those areas.
Software is another discussion and one a lot more based on preferences and its been discussed to death so no point going into that.