When did a PS5 become a unit of cost? For reference seems to be about 0.002 London buses
I think it's intended as a comparison of cost when building a gaming-capable computer vs. a console of somewhat equivalent power. It used to be a general rule of thumb that you could build a computer of roughly equivalent power for the cost of a game console, or a little more — now the memory costs more than the whole console.
The PS5 has 16GB of RAM. One can buy 16GB of RAM for ~$100 [1].
[1] https://pcpartpicker.com/product/9fgFf7/kingston-fury-beast-...