You can spend a fortune on a PC today but you don’t have to. The majority of popular games are developed for the lowest common denominator. Even a £500-800 PC is sufficient for enjoying popular FPS at decent frame rates. I have a 4070ti super and rarely bother with things like ray tracing or playing games at Ultra. Very high settings produce sufficient eye candy at 4k.I see these days motherboards can cost several hundred alone, then a couple of grand for the GPU, cases again a few hundred. Top end PC kit these days certainly isn’t cheap. Plus if I built one these days I’d water cool everything I could.
There are countless of videos on YouTube of super powerful computers but some of them are by YouTubers who borrow components from manufacturers.