That's kind of disingenuous. If you really have that usage scenario, then don't use an iPhone 7 ... or get a new MIDI adapter at the same time as your phone. I could complain that my ProTools NuBus card doesn't work with my Mac Pro, too.
Uh, no. Disingenuous is claiming that the headphone jack had to be removed to make the iPhone water resistant/proof and thinner. Clearly, that is absolutely false since the OnePlus 6 has nearly identical dimensions AND a headphone jack.
I should not have to buy hundreds of dollars in additional peripherals because Apple wanted to squeeze everyone out of another $20 (when their lightning to headphone adapter breaks) or $170+ if they decide to get the Apple wireless headphones.