>>11816550PC Engine, not Mega Drive.
As the Mega Drive only did 3.65 million units in Japan, and even the PC Engine floundered in it's later years due to NEC over charging for the Duo systems and not bothering giving needed upgrade to the PC Engine hardware (nothing in the vains of the Super Grafix but rather things like a built in multitap, 128KB of built in storage, S-Video and RGBS out of the box, 2-4X CD drive support (the original CD Interface Unit even supported faster drives as a form of future proofing which NEC never bothered with), built in Arcade Card, ect.) which allowed the Super Famicom to gain it's footing.
But once the PS1 showed up it took until the Nintendo Switch to have Nintendo get back it's market share, not from Sony (as Microsoft is a joke in Japan) who already lost the Japanese market by 2012 and moved PlayStation to California in 2016 as a result but rather mobile and Japan never looked back since 2017, so much so that Sony moved some of PlayStation back to Japan which resulted in a 3rd PSP to compete against the Switch 2 Nintendo controls that much of Japan's market share.
Nothing Nintendo Power pushed was garbage as those flash carts were Japan only, plus Super Mario Bros DX was a proper rom release interannually.
Super Famicom wise Nintendo Power (besides rereleases) was mostly just puzzle game, Picross (8 of them, 10 counting 3rd party releases) and text adventures.
Game Boy Nintendo Power originals were just Super Mario Bros DX and Balloon Kid DX.
Rare saved the N64, so much so that their investors forced Nintendo to sell Rare off to Microsoft just to focus on the Japanese market, this resulted in Nintendo being 2 generations left behind.
The lack of Sonic, the split DRam and SDRam set up of the Saturn and the use of quads instead of tris is what killed the Saturn, it was even said that in Japan the only thing that people were buying for the Saturn was Virura Fighter and Sakura Wars as the PS1 was otherwise Japan's main focus.