Things to take into account:
Many people when purchasing a computer go for more expensive is better rather than finding a machine that genuinely fits their needs. At the office I worked at, the computers were recently upgraded. To what, you might ask? $1200 machines that did little more than access a web program and Excel. Other people will buy an $800 machine to do what they could accomplish on a $200 Chromebook. Not everybody shops smart.
Despite whatever that study found about building computers, I can practically guarantee a vastly larger amount of the market is people who buy pre-made machines, whether they be towers or (the one you want to buy pre-built) laptops. Not to mention that the PC is kind of a "do everything" device, so trying to compare total general PC hardware sales to dedicated game console sales is apples to elephants. Just because somebody bought a PC doesn't mean they're going to do a lick of gaming on it.
Which comes to the next point. Inevitably, somebody, somewhere likes to bring up the 200+ million or however many total Steam users. Let's recognize what that number means though. That number exists because buying PC physical is very nearly dead. Almost nobody does it because of CD keys and the like making resale a moot point. If you game on PC even a little, odds are you have a Steam account, whether you actively use and purchase with it or not, as it is the most prominent PC gaming marketplace. The number of Steam users almost says nothing about PC gaming outside of the context of console digital marketplace numbers compared to physical purchases.
Now, PC gaming is growing in popularity, although it comes with its share of entry barriers. PC gamers really need to stop flaunting the fact that everybody owns a PC, or millions of people own a Steam account they rarely use, or the fact that free to play titles are very popular, as game console killers. The markets are still fairly separate, although they're slowly merging with things like Fallout 4's mod support, and Microsoft's attempt to basically make the Xbox One and PC a singular idea.
It needs to be accepted that PC gaming is slowly growing, with home consoles having the better part of a 20 year head start before many game console developers started taking PC seriously. Many console focused game developers are still taking their first real leaps into PC gaming, or are just learning what it means to optimize for varied PC hardware despite multiple PC releases. PC is not yet a gaming juggernaut. It is not yet gaming nirvana. By the time it reaches that point, I feel like game consoles will be more of a budget PC option than they basically already are anyways, which will essentially eliminate the debate between consoles and PC in the long term.