Well for one thing, who can complain about an article written by time travelers? I mean the article is a 2018 update while the rest of us mere mortals are still navigating 2017.
It looks like they brought back their top choice from the future since that 7 Ghz Quad core is quite impressive. Nearly 1.5x faster than the fastest CPU made by any manufacturer in 2017.
Apart from the fact that there aren't any ACTUAL facts about their assertions, the article is chock full of grammatical errors and basically sh!t.
On a serious note, let's address the issue here with some actual 2017 info.
WiFi (regardless of the band, letters, speed and so on) all suffer from the same issue, interference. This interference comes from other devices operating in similar ranges, microwaves, and physical things like floors and walls. If your router is in the basement and you want it to reach the 2nd floor on the opposite side of the house, it just isn't going to happen.
Your best bet (assuming the router has to be in the basement for one reason or another) is to get a network extender and place that on the 1st floor. Now the signal from the router in the basement will be nicely boosted to the 2nd floor and you will be fine.
As far as gaming goes yes having a fast connection is important to avoid lag, but I can almost guarantee that your local WiFi connection is going to be faster than your external Internet connection.