The real reason behind the NES Classic Edition's short controller cord explained?

This explanation comes from a fan, albeit one that seems very informed on the technical side of things. The explanation isn't from Nintendo themselves, but it certainly seems to be a plausible one.

- NES Classic Edition controller can be plugged into the Wiimote
- it acts as a Wii classic controller with less buttons and no analog
- this is the same port the Wii Nunchuk uses
- the Nunchuk transfers a fair amount of data to the Wiimote itself
- the cord length between Wiimote/Nunchuk was due to the data from the gyro and the buttons
- the cable itself has 4 leads inside:

3v
clock
data
ground

- communication protocol used is I2C
- this protocol was designed in 1982 by Phillips (now NXP) and was designed for "high speed" chip to chip communication
- the limitations are speed and length
- length of the NES Classic Edition/Nunchuck cord is 50pF
- this is the maximum you can get from a yet-flexible cable
- a thicker cable would have been more expensive and less practical
- extension cables are pushing the limit of the protocol
- using another communication protocol would have made for a controller not compatible with Wii and Wii U
- this would have been expensive to design and manufacture