When there is a cross-generational time they sell new games on older systems and yeah sure a few plebs complain, but no one cares and it doesn't seem to bother the console makers any.
I really doubt the difference between the $400 and $500 hardware would be a deal breaker for console audience. If you look at the specs the only difference is in the GPU unit. It's basically swapping a video card on a PC.
You're not really refuting the point here. Cross-generation games... $100 difference in hardware (Xbox 360, PS3, PS4)... both those things mean the games are developed for the lowest common denominator. You're literally listing examples of what I am saying will happen.