About GB>DS trasition, its important to note that DS was not intended to be a substitute to gba, but a 3rd line of product from nintendo, but the success of the machine was so strong that they problably just decided to stick with it.
Another counter point: sega did the same, and at that time, was the only competitor that managed to make some treat to nitenndo bussines, while atari and their numbered proposals failed one after another.
But why don't microsoft and sony do the same? because they do much more than just consoles.
When you call a nintendo, you are sure its a videogame, but a "sony" can be a smartphone, TV, etc. The same with microsoft. Nintendo is know by their bussines in game market, they don't really needed a brand.
Another point: fail is what when you try and don't succeed, but Nintendo didn't tried.
"Hardware design isn’t about making the most powerful thing you can.
Today most hardware design is left to other companies, but when you make hardware without taking into account the needs of the eventual software developers, you end up with bloated hardware full of pointless excess. From the outset one must consider design from both a hardware and software perspective."
Gunpei Yoko
