Your point is fair that it's not always going to be that way. But it's not clear when that change will happen. And Sony made a huge blunder in price on PS3, and Xbox followed with a huge blunder on price in 2013.
Remember that games were $39.99 in 1978 and held until 1985 when they were $49.99. That held until 2004 when they went to $59.99 (and yes, there have been outliners through the years, but those were the mainstream prices).
So gaming seems to fight inflation (and is a killer deal today relative to gaming back in the 80's and 90's.)
(link to one of my favorite graphics:
https://www.reddit.com/r/gaming/comments/92djek/console_prices_adjusted_for_inflation/)
There is also the global problem where different currencies and duties make consoles even more in other nations. So that extra $100 could have a big multiplier when it comes to tariffs and taxes around the world.
My guess is that by the time consoles are "mainstream" at $499 is when consoles don't sell as high volumes anymore.
Despite what
we all want in a console, price generally beats performance at scale. If it didn't, you'd see both the PS4 Pro and Xbox One X being the volume leaders. But last time I looked they were both hovering around 25% of the total mix per platform.