Likely the cable but not the phone itself. The pro cameras can create images and video that have large files. Even without the EU law, Apple needed a faster way to pull these files than todays lightning connector can provide.
[0]: https://www.apple.com/shop/product/MK0W2AM/A/lightning-to-us...
That would be a messy enough solution that they might as well have just switched to USB-C instead. Which they have done.