Which game developer makes the best console games?

You said console games right? The answer is undoubtedly Nintendo EAD/EPD.

How many developers were so good that their strength alone carried the entire console for several generations? After the SNES era, Nintendo badly burned bridges with many companies (they had really strict licensing terms) including Sony (failed to develop a console with them), Sega (obviously a rival), Squaresoft (which left to Sony) , etc. From the N64 days to the Wii U days Nintendo was essentially crippled by a lack of great third party developers. Only now it is starting to change because of the success of the Switch. The N64, GameCube, Wii and Wii U were carried almost solely on the strength of Nintendo EAD’s first party titles. How incredible is that? And unlike other developers, Nintendo has never released a game for PC yet and only recently with mobile with Super Mario Run and Pokémon Go.

Nintendo EAD/EPD has created some of the greatest video game series of all time including Super Mario, Legend of Zelda, Animal Crossing, Wii Sports/Play/Fit/etc, Star Fox, Donkey Kong, Metroid, Fire Emblem, etc you can see that Nintendo’s first party strength is so strong that they basically sold 4 generations of consoles based on the strength of its first party alone (actually 5; because everyone knows that people buy the Switch for only 4 games: Super Mario Odyssey, Zelda Breath of the Wild, Mario Kart 8 and Super Smash Bros Ultimate, which is all Nintendo EPD)