I'm confused since the audio port is accessable from the top when docked.

Ohh I'm sorry, did you think was witty or something?

Nintendo could easily choose to either put a microphone on the Switch or the joycons/pro controller, as they did with the DS, 3DS, Wii and Wii U, or put the microphone jack in a location that it's accessable while it's docked. These are choices Nintendo made that they technically were not forced into due to other critical aspects of the design that did they could not reasonably change. All of the PCBs in the Switch are custom, as is the casing. That means that they could put the microphone jack where ever they wanted. Also, considering the inclusion of a microphone would cost Nintendo about one cent per unit, it likely cost Nintendo to develop and maintain the Nintendo App on phones than they would ever spend including a microphone, there's no cost reasons either.

There are no technical reason why Nintendo couldn't have have voice chat built into the Switch. None.

Still struggling I see.

Mic in Switch, useless when docked.

Mic in joycon, useless for motion control games like ARMS/Just Dance.

Switch is built for portable gaming and 2 player gaming. Using a smart device is a better solution.

That doesn't even matter. Nintendo chose to put it in the body of the Switch itself rather than in the controllers like Sony and MS does.

If only there was a way for two devices like a headset and a console to communicate wirelessly. If only there was an adapter to send and recieve wirless signals and convert them into a signal used for a headset jack... maybe then someone could come up with a solution. Ohh well.

Idk, it'll feel kinda weird playing ARMS with motion controls. Plus you have to consider putting outlets for both joy cons.

You think headsets are suited to games like ARMS? Not very portable either, are they? Sounds like a lot of messing about when you can just use a smartphone.

Sure, why can't headset be suitable for games like arms? I don't know, how do athletes manage to listen to music while they're running/training/at the gym?

They must be magicians!

So we're adding the cost of upto 4 wireless headsets for ARMS and 8 wireless headsets for Just Dance.

Do you see how silly your 'solution' is when you take into account motion control, price, simplicity, local multiplayer?

You're right. That sure is more expensive than 4/8 cell phones. Yup.

Microphone array then? Worked plenty fine on Wii and Wii U. They can offer multiple voice chat options, including the phone app. It doesn't have to be just one.