I also think the price comparison is disingenuous, as you have to opt for Apple's very expensive upgrades to get even close to the price of the MBP.
The MBP is also upgraded, but the SSD upgrade (most important IMO) comes stock in the MBA, and adds at a minimum $200 to the MBP. Much more if you actually go with the 512 GB as the author suggested.
The stock MBA is plenty powerful for your average user, and hundreds of dollars cheaper than the MBP.