Which is weird because most iPhone users use all the power for stuff like WhatsApp. iPhones are plenty fast already (honestly probably mostly due to a well cared-for UI).
I assume Apple wants the phones to have the most efficient CPUs, since battery life is much more critical than laptops & desktops.
It’s my opinion that Apple sees putting the best processors in iPhones as being able to extend the life of the product. With that available compute overhead today it will feel “faster” longer and can take advantage of software features they develop 1-3 years down the line.