I don't agree with the conclusion that this article made.
because it doesn't make sense to roll out the feature in places where mmWave spectrum just isn't in use.
It said previously that mmWave was very useful when there were a lot people like in concert or sport games. So everyone may need mmWave. Even in a country that hasn't supported mmWave, having mmWave is future proved. Remember, average people will use a phone more than 3 years.
In a nutshell, no, most people don't need mmWave connectivity, nor will most people even access to it on a regular basis for the next several years to come.
For me, Sub-6Ghz and mmWave in 5G are just like 2.4 and 5G in Wifi, there is no need to explain any further.