Rather than getting into the ins and outs of why they did it, who misses the jack, who doesn't, why can't we just agree based on the wealth of commentary here and elsewhere that for a significant minority - possibly even a very
large minority - this removal represents a disproportionately high impact change?
It's like admitting that people are entitled to mourn the removal of the jack is part of a slippery slope toward admitting that Apple - gasp - made a mistake, and that's just untenable.
Apple makes a ton of money from this - they're one of the main BT headphone vendors - so I actually don't consider it a mistake on their part (they know exactly what they are doing) but for other manufacturers it makes no sense. No-one buys a phone because it has no jack. Some people though will rule phones out for dispensing with the jack. So why do they do it?!
For me for example, it's literally the first thing I now consider: I will not buy a jack-less phone while alternatives are available. Don't care about camera, brand, etc - any mid range Android with a jack will pretty much suit me.