Adjusted for inflation the PS2 was $395 on release, the PS1 was $446, the PS3 was $567. When the NES was released in 1986 its price was $412 adjusted for inflation.
As an "amateur historian of video games" I figured you know that 400 dollars is almost average for a system's price.
Also on the "amateur historian of video games". Being a historian includes having a level of impartiality in your assessments. This article comes off more like an XBox fanboy pissed that Sony is actually selling more systems. This article was seriously a waste of time to read.