The Series X specs are higher then 90% of PCs currently used on Steam. And for half the price with the added benefit of being more compatible with entertaining groups while hosting.
PCs have their place and plenty strengths, but consoles have always been more cost effective and convenient.
PC gamers care less about convenience and cost (many of them, anyway). That's something always thrown about, but means little in the end. If you want the superior experience, you build a gaming PC.
On top of that (I always have to say this too) the Steam survey tracks a fraction of the segment of PC gamers out there. Just based on the benchmark world, alone, plenty of people have PCs that already crush both upcoming next gen consoles. That's just how it is and will only be worse at launch (when the 3000 series arrives).
Of course there are many PC gamers with high end systems that aren't part of the Steam survey. But there are also many more PC gamers with low end and average PCs that aren't part of the Steam survey.
And I doubt that the percentage of high end PC gamers in total / without Steam is higher than the percentage of high end PC gamers shown in the Steam survey.
Why should high end PC gamers overproportionately avoid Steam? These hardware enthusiasts often are very active gamers which won't dispense PC games that are only available on Steam.
Or why should Steam gamers with high end systems overproportionately deny the hardware survey? Most of them are proud of their hardware and want to show the specs all the time. Even if the survey is anonymous probably more Steam gamers with low end systems will deny the hardware survey than people with high end systems.
So the absolute numbers of PC high end systems will be a lot higher than higher than "active Steam users x GPU percentage), but the percentage shares of PC gamers with high end systems will probably be lower than shown by the survey.
And how many people are participating in the "benchmark world"? A few thousands per month, a few tenthousands per year? IMHO the Steam data is much more representative than benchmark data collections.