PCs are more expensive because they can do everything.
This is the main reason why I favour PCs. It's a huge step backwards to go from general-purpose computers that can be made to be good at any computing task with the right components, to locked-down computers that are only designed to be good at one thing, and then only for games that target that specific console.
Related to that point, consoles also fragment the game market. I can buy a PC from Lenovo, Dell or Apple, with a CPU from Intel or AMD, and memory, storage and graphics from countless other vendors, and it will play the exact same set of games (give or take performance and OS requirements) once I install Steam. I don't need to base my hardware decisions on which games I want to play, aside from getting a powerful enough PC.
With consoles, you have vendors who compete not only with their hardware, but also with the selection of games available for their platform. As a console buyer, you would need to base your choice of console hardware as much on the games available for each as on the capabilities of the hardware itself. As soon as you want to play two or more games that don't both target the same console, the cost argument against PCs becomes null and void, as you now need to buy
multiple systems to satisfy your requirements.
This argument should be nothing new to anyone acquainted with the progress computer science has made over the last 70 years. There has been a tremendous amount of work in moving us from multiple incompatible systems (like today's consoles) in the '50s and '60s, to operating systems portable across multiple hardware (like today's Linux) such as UNIX in the '70s, to applications portable across multiple operating systems (like GNU) in the '80s and '90s. Finally, we have arrived in the 21st century, where we can take portability for granted, and everyone wants to go back to the days of mutual incompatibility at the hardware level.
Consoles make no sense, economically or practically. (SteamOS consoles excepted, since they are PC-compatible.)