As someone who games exclusively on the PC, you're smoking some good shit. Try TRIPLING those prices and then you've got a decent system.You would need the following components to build the PC:
Motherboard - $75
CPU - $50
CPU Cooler - $25
Thermal Paste - $10
RAM - $50
GPU - $250 to $300
Power Supply - $50
SSD - $50
Case - $25
Case Fans (this isn't 100% necessary depending on the type of case and if there are built-in fans with it) - $0
Keyboard - $10
Mouse - $10
Operating System - $0
An RTX 2060 Super by itself would cost between $250 to $350. An RTX 2060 Super is barely more powerful than the PS5, and a regular RTX 2060 is not as powerful as the PS5. That is half of your budget in the first component. Just the cost of the motherboard, CPU, CPU cooler, thermal past, RAM, GPU, and PSU puts you over your $500 budget. That is a total of $510, and we haven't even factored in a case, case fans, keyboard and mouse (which are a requirement for PC), or an operating system.
Additionally, all of the components above are used. This means that you're getting the leftovers that generally have no warranty and you're S.o.L. if they fail during or after your build is complete. There is zero peace of mind for someone building this system. By contrast, there is peace of mind by purchasing a PS5 or Xbox Series X instead. I'm a PC gamer, and what you're saying is not only patently false (you can't get the components you need at the price point you said), but even if you could get close I would never recommend this to someone wanting to jump into PC gaming.
PC gaming is awesome. But it's an expensive hobby. You get what you pay for (generally speaking), and your statement will get someone a garbage setup with sub-par performance. And on top of that, it's extremely risky as so many of these individual pre-owned components could fail and cause a ton of headache.
PC gaming used to represent good value for money. Now it's fucking retarded.