The average PC gamer basically has a system that has the performance of a PS4 from 2013.
And it is clear most PC gamers can not afford a full system upgrade that would rival a PS4 Pro, let alone a PS5. Not only is the 1650 still the most popular PC GPU, the 1060 3GB and 1050Ti are still extremely popular too.
You can basically argue that the majority of PC gamers have stopped upgrading or switched to consoles. The remaining PC gamers likely play indie games now, or older less demanding titles that still run on their systems, you can clearly see this from game sales figures.
The fact so many PC gamers run very old hardware, has to do with Nvidia and AMD's outrageous GPU prices.
This cost is also related to the fact that PC don't have a unified architecture like consoles and ARM have. When a PC gamer buys a GPU, they are buying a second PC. GPU on PC have their own controllers, memory pool, power management, cooling, etc. That drives up the cost like crazy for PC, the GPU alone costs as much as a console. Managing 2 different memory pools also introduces lots of performance bottlenecks along the way, where PC can't load assets into video memory as fast as consoles. PC bandaids like DirectStorage need to be introduced, yet PC games continue to struggle with stuttering.
PC gaming is really in shambles right now. You have the outrageous cost of GPU, tons of PC gamers who can't afford upgrades, the shader compile stuttering on PC, asset load stuttering from a lack of unified memory, developers that don't care about the platform and release horrible ports, etc.