This is a report, nothing more. But It wouldn't surprise me to see the 15 still use Qualcomm. But the 16 would be a bit surprising. Even Qualcomm themselves had noted in an ER that much of Apple's business would soon be gone.
The iPhone 16 release date would be 5+ years since Apple bought Intel's model division. Presumably a division that could hit the ground running. 5 years is a fair bit of time to not have created something ready for production.