They definitely could, this doesnt seem to happen for a lot of things though unfortunately.
HTC used to do this too. I had a touch diamond which was big enough for a headphone jack but instead you had to use their PROPRIETARY usb jack instead. You either had to use the shitty earphones that came with it or buy a bulky and inconvenient adapter, which meant no audio out while charging (hope you weren't planning on using it in a car or something).
I thought the industry grew out of dumb stuff like that like 5 years ago. I guess we have a new usb plug now and everyone is freaking out again.
Except if you want to charge the phone while listening to music.
Not every innovation is an improvement.
Don't worry. You'll be able to buy a $50 splitter for that.
The phone from the land of nope....
Edit: Why would I wnat another device with a battery and a phone with smaller one? Battery have stagnated too much for me to be willing to switch. On top of that the audio quality isn't there for sub $50 Bluetooth headphones for me to consider. I understand the "don't buy it if you don't like it" I won't. USB C to 3.5 mm isn't quite there yet either.
The race for making technology worse. Phones getting thinner and thinner, without ports for useles purposes in my opinion. Why would I care to carry around a thousands accessories to attach to my phone? Isn't that more inconvenient than carring a bit of a bigger phone that self contains almost everything an average user might need? Also back covers hold on the phone with magnets to me sounds like looking for troubles. We'll see if a solution like that will hold to the everyday life.
I don't like the removal of the headphone jack because I like my wired earbuds, I don't care about a little cable, I don't have to charge them all the time and if I want to charge my phone and listen to music I can. What if I still want to listen to music and charge my phone? I'm screwed. I have to use bluetooth earbuds and keep them charged. Since I'm a heavy music listener bluetooth headphones are not something for me.
As much as I don't like Samsung because of the choices made with the software I have to admit that the Galaxy S7 Active looks like a great all around phone, except for the speaker.