JongAm Park

I doubt if it's good idea. Well, saving $ on components to bring 3.5mm audio output will be  a lot to Apple, though.
I remember that how much Samsung Elec. made an effort to cut the numbers of screws bolts in their notebooks computers in 90's and they said it will save lots of money for production. Especially saving money on A/D converter chip in iPhone can be significant. (3.5mm audio is analog, while bluetooth and lightning audio out is digital.)

However, this will bring interesting topic to people who use iPhone to broadcast, record audio for interviewing and so on.
Recently I had a chance to search what kind option there were for recording better audio, and shotgun mics, condenser mics, wireless mics.. all of them used 3.5mm audio jack. To people who already have those will need to buy a new one if they upgrade their iPhone to the new one without 3.5mm audio out port. If they want to use one mic/audio device requiring 3.5mm with other phones like Android should buy an another one with 3.5mm audio plug.
To manufacturer it can be good and bad at the same time.
This change can spur people to buy a new mics and audio devices, so to manufacturers it can be good chance to increase their revenue.
On the other hand, it can be bad because they can't get benefit of economies of scale. So, cost for producing such audio devices can rise.

So.. which is better to customers?

Apple has interesting issue with this also.
USB-C is already being adopted by other Android phones. MacBook uses USB-C. Probably MacBook Pro can have USB-C ports also.
USB-C is small enough for iPhone... then.. why should they keep the two standard? Ligthing and USB-C?
If they choose only one, for example, USB-C, those audio devices can be hooked up with iPhone and Mac ( and iPad).
Are they going to ditch lighting port for USB-C?
Or they will wait for a few years until customers replace their peripherals using Thunderbolt (mini display port) to USB-C (with Thunderbolt 3 protocol) and then ditch lightning port on iDevices with USB-C eventually?

I hate this game.

Best way to say Apple to stop making such restrictive machine is not to buy them.

For the price of MacBook, only 1 port? The keyboard is even not as good as the one in other MacBooks ( Air/Pro ).
Old MacBooks (white/black) and Pros had nice and easy way to upgrade memory/HDD.
I don't think it was bad design-wise. Why does Apple keep making MacBooks and even Mac minis even more restrictive?
What's the good thing of not having replaceable battery, upgradable memory and storage devices?
Just to make MacBooks world-most-slim, is it good to remove such freedom?
4GB for MacBook Air/Pro is too small for me. 8GB.. questionable, but their price jumps. 16GB? Right for me, but too expensive.
Why not allowing buying memory and storage devices from 3rd parties or give us freedome to wait another year when price would drop. Then we can upgrade our machines at that time with newer memory and storage devices.
Isn't it common sense we have had from 70's and 80's even 90's?

Just don't buy Apple's product if we love Apple's product. That's one good way to tell them what's right for customers.