Could be yes.
They started with Infineon modems in the first iPhone models.
Infineon later was swallowed by Intel and has become its modem division.
Qualcomm has such better and faster modems, with support tech used by T-Mobile in its latest MIMO deployment for higher speeds.
I always buy the unlocked models anyway and I wait for the first production batches issues to be worked out.
A1660 (iPhone 7) and A1161 (iPhone 7 Plus) are the models to get this year if one cares about max. band support/ world traveling.... or just resell value so the phone can used on all 4 carriers in the US.
I don't care about the 3.5mm jack personally. I have been using BT in the car and with earphones and headphones for years. I never even took out the Apple-supplied earphones from the box since the iPhone 4 I think, they produce terrible sound (partly because in my case they don't fit my ears well).