I think he's talking about the extreme end of dedicated PC gaming hardware. It would be completely ridiculous if he meant the overall PC gaming market.

Still think he's wrong mind.

PC games have longer lifespans than console games so it is hard to compare.
Take WoW for example, now 10 years old and still 7 million active subscriptions.Impossible to replicate on a console because console lifespan is 6-7 years.
PC gaming market is far healthier than 10 years ago.
Digital distribution saved PC gaming, console gaming will struggle with that transition.Will a 6-7 year old kid be able to work it out? Next generation we will see the last of the physical console games IMO.

I've always thought pc gaming was more niche

That means so litle you will be shocked. For all those talking about YOY sales please try and understand this.

On Wednesday afternoon, NVIDIA Corporation (NASDAQ: NVDA ) reported stellar Q4 results. Revenue grew 9% sequentially and 3% year over year to $1.14 billion, which was well ahead of the company's guidance range of $1.05 billion plus or minus 2%.

NVIDIA's strong results were driven not by its growth initiatives in mobile computing or cloud-based graphics processors, but by its core GPU business.

As a result of strong demand from gamers and market share gains, NVIDIA grew sales of its high-end GeForce GTX GPUs nearly 50% year over year in Q4. This was the primary factor driving 14% revenue growth in the GPU business, which more than offset a year-over-year decline in sales of Tegra mobile processors. Strong sales of high-end GPUs also helped NVIDIA post record annual gross margin of 54.9%.

So lets break that down. So sales as a company greaw 3% YOY and it had highend GPUs to thank for that. Remember, "highend" GPUs typically cost anywhere ebtween $500 and $1000 and then some. But lets put it at an average of $750. We are talking highend GPUs as nvidia clearly stated. Not mobile or general average GPUs. They also said it was responsible for 14% growth revenue. Now they made $1.14B of overall revenue in that quater. So lets extrapolate that to a cool $4B for 4 quaters. Now lets say 50% of all that revenue is due to highend GPUs and ignore most of what else nvidia does as a business (impossibly high estimate but this outlandish estimat will help put things in perspective).

At $750 average for a high-end GPU, and looking at $2B in sales... we are looking at yearly sales of 2.67M. Mind you, if you really take everything into consoderation, its impossible that nvidia is selling this many GPUs with an averag price of $750. Its probably around half that at best. So coming and just saying YOY growth or whatever is up really doesn't mean anything besides sounding and looking good on a investor report. Oh and two words "BITCOIN MINING"

To OP:

PC gaming has and will always be a niche. Its just becoming a very very very very very loud niche. But its still a niche regardless. Its just like looking at fans of a certain platform on these forums. If you go by post count or how many they seem to be you would expect that platform to outsell everything else. But that platform ends up seling less than a third of what the leading platform is selling every month. Thats how PC gaming is too.

That kind of depends on what NVidia mean by high-end. They could be including anything down to a GTX 770 (which they describe as "high performance", could even be a 760 which they describe as "powerful") which can be bought for $330, up to a Titan Z at $1000+. The GTX 770 alone would sell far more than the other products for the sole reason it's cheaper (check the Steam hardware survey and you'll also see it's one of the better performing DX11 cards).

That completely throws off your average of $750. Then you have to remember that the money a consumer pays for that card is split between NVidia, the card manufacturer (e.g. Gigabyte, EVGA) and the retailer.  Basically, you're calculations are pretty far off base.

Edit:

PC Gaming has always been niche? Over 75 million Steam users, 8+ million sales of Starcraft 2, Diablo 3, Half-Life 2, 7 million subscribers to WoW, DFC projected growth of 10% CAGR.... and it's niche?

Were they ever mainstream?

Thank you. Of course my calculations are far off base. I was actually being really really really generous. Its easy to spin things around and look for loop holes than make thing seem a lot better than they actually are and that is why i chose to be somewhat unrealistic. You can say it depends on what nvidia considers as high end.... but when looking for a real average, we are supposed to add up the individual prices of all the dedicated GPUs nvidia makes then didvide that by the number of GPUs available. If you did that. Even taking $150 gpus into onsideration all up to the $3000 GPUs, you will see that you end up with an average much higher than my $750. And hen you look at sales, i didnt take a ton of things into consideration cause I wanted their sales to be really really high.

Even at those really really high sales, we are still looking at less than 2M sales per year..... in reality for high end dedicated gpus this is actually way less than that. And that is the point i was trying to make. YOY growth doesn't mean anything cause its not really painting the full picture. And fot all you know, they may have sold 750K dedicated GPUs last year then sell 1M GPUs this year and be trumpetting YOY sales growth. That doesn't mean shit.

If they "really" were doing so groundbreakingly well, they wouldn't be giving percentages... they would be showing off hard cold numbers and saying we sold this and that million GPUs last year bla bla bla.... whenever you see a company talking more about percentages or YOY sales instead of just giving hardcold numbers... then you know they are hiding something. Its literally the business defination of the word "spin".

Never. It will just go more niche. And from the comments I guess many people didnt read the OP, commenting based on the title.

I guess they were back in PS1 and half of PS2 when consoles didnt have online, or good online. That used to be a huge selling point for PC gaming which it lost.

Yup. But it seems bigger because of some vocal minorities. But when it comes to being mainstream, consoles always have an upperhand.