It was not a general comment - if you care to read the original post (which you seem not to have done)
The interesting question for me would be if Canon came up with a new camera line for high resolution should it be priced above or below the 5D line?
Since Nikon is undercutting Canon's current prices (in fact the new Nikon D750 looks very much like a strong 5DIII competitor on the specs and only costs 2.300$) Canon could hardly bring anything on the market with much less than 36 MP costing much more than 3.300$ without getting flak for being either under-performing or over-priced.
If Canon brings us a 8.000$ camera as their answer to Nikon's 3.300$ D810 I for one would "save" the money, buy a D750 and D810 and use the balance to sell my current Canon line-up for Nikon's equivalent. YMMV.
I specifically answered to how current Nikon models compare with the 5DIII and what this may indicate for the price of a possible high MP Canon 5DIV - where I pointed to the fact that the Nikon D750 which is very closely specked to match the 5DIII is far cheaper (also in Japan) while the D810 obviously has the MP the 5DIII does not. Leading to my conclusion that "Canon could hardly bring anything on the market with much less than 36 MP costing much more than 3.300$ without getting flak for being either under-performing or over-priced."
[Apart from that Amazon.jp is not a good place to get current info on Japanese camera and lens prices as their prices sometimes are far from the best.]
Well of course the D750 is cheaper than the 5DIII, it's about 18 months late to the game.
if it were priced same as the 5DIII no one would buy it. Plus those who waited have already bought a perfectly good D800, D800E, D810 or even made do with a D610. So now this comes along and has to compete with all that so it's priced to match.
So you are judging the future price of a mythical camera on the difference between these two cameras?? And you jumped to the conclusion that it would be $8000?? That don't add up at all. Based on the difference between the D750 and 5DIII the high megapixel Canon offering would be about $700 or $800 more than what the (then old) D8xx would be. New vs old? Hmmm, Well that seems reasonable, don't you think?