I think it's really hard to "prove" if you save one way or another since everyone has different buying habits. The cost of PS+/XBL, the cost of extra controllers (if you're doing local, either on PC or console), the cost of hardware, the cost of a headset, etc all play a role too.
But the cost doesn't really matter to me. Last PC I bought was 2 grand and I'm in better financial shape now than I was then. That thing sits and rots in the corner (reminds me that I should reimage to a friendly Linux distro to get some use out of it). The argument always goes back to convenience, in which case the PC always, always loses for me. I say that as someone who works daily with various Linux distros and has been a PC gamer since my dad taught me how to boot a .EXE in a DOS terminal.
I don't enjoy working with hardware. I don't enjoy tweaking software. I don't enjoy finding the best deals and planning out how to save some bucks on PC components and then creating the ultimate build. By and large, that's already a part of my job and it's something I've done since I was a teenager. I am older now and I make good money. If I have the opportunity, I make it a point to purchase something that saves me time.
PC is just too much of a timesink. There's a significant amount of freedom on the platform but the one thing it lacks is uniformity and ease-of-use. You like voicechat? Well, that isn't exactly native in the box. You have to buy extra hardware and probably install one or two software packages. You like recording gameplay? Either buy a capture card, appropriate software, and/or a compatible graphics card.
On the other hand, I can purchase a PS4 game on store.playstation.com and have it downloaded and ready to go by the time I come home after work. That's possible on PC but not as a native feature. I can record and upload footage without having to think about it on PS4. Not so on PC. I can start broadcasting a stream mid-game, start a chat party, let someone else play my game, follow someone else's stream and a whole lotta other stuff native on PS4 but can't necessarily do that on PC without having to set up a wide suite of different software and services.
Other than the occasional weird glitch that requires a reboot, my PS4 sleeps and boots right up whenever I want it to. I had -- at the time -- an extremely fast PC build with SSDs and all of the crap in Windows 7 disabled and my PC still took about 20s (which was still lightning fast compared to what I grew up with). One could argue that the PS4 might break.... well, I've had my fair share of dead PSUs, processors, and RAM sticks over the years. It's typically more expensive to repair a PC unless you're willing to wait for a deal, in which case you've lost another one of your advantage over consoles since the wait is as long (or longer) than if you'd sent in a console to the manufacturer for repair.
It's just a matter of convenience. PC is only cheaper if you navigate an always-changing labyrinth of deals, exploits, and seasonal sales, and in the process you lose a whole lot of time.