Setting aside for the fact that these "leaks" are still rumors from unnamed sources.
When is a game company *NOT* thinking about new hardware? Doesn't mean it's actually what their next system will be. Doesn't mean it'll be released next year. Nothing about this source says that it'll be another DS system, anyway. They sourced that Nintendo is cutting a deal for the Tegra chipset, which is mobile technology, but they have nothing but guesses as to its implementation. The article itself admits that reviving the Gameboy brand for a single-screen unit is possible (1st page, 2nd to last paragraph).
So there is, in other words, no way of knowing what type of hardware the chipset is being used for, what features it will have, what it will and will not be compatible with, or at what point Nintendo may cap the processing speed in the interest of battery life. For all we know Nintendo themselves may not have finalized that yet. No need to jump to conclusions.
As for the developer part, blame them for thinking that because a system had X feature, they needed to use it in X manner, even if it wasn't particularly beneficial to their game design.
Very true. Even Nintendo themselves ignored such features once in a while. There's no pointing in Brawl or in Fire Emblem Radiant Dawn. Hell, those of us who've checked out the homebrew community know that the DS doesn't even need to keep both screens lit. More than any unknown policy by Nintendo, the issue is more likely the game developer's fear of public/reviewer backlash at the perception of not using the system's features to their fullest.
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