All of them, if there was just one the console gamer would be screwed to no end. Both with pricing and content as well as hardware due to lack of competition.

A few years ago I would have suggested nintendo. But not anymore. Its sony.

Case in point, pricing for ps3 and anti consumer policies ms tried to shift this generation, but backed out of due to backlash and ps4 being vanilla, essentially breaking their legs before gen even begins.

Worst case scenario if there was just one console, we will have a piece of shit console with a price point of £1000, 3 wheelbarrows of dlc upon every release, not being able to sell the games on or lend them to your friends and always have to be online to play the games.

You don't think someone else would just fill the market demand? The market is many many MANY billions in size, and more than ever before, the PS4 and XB1 are basically a pile of PC parts thrown together with an SDK and proprietary OS.

I think we'd see a Google or Apple console within a short time to fill the void. I mean we've seen :

Atari, Coleco, Intellivision, Sega, 3D0, SNK, NEC, etc all come and go over the years. I just don't see the industry disappearing without Sony and MS. Too much money to be made. Of course it wouldn't disappear without Nintendo either, but I think the loss would be much more uniquely felt. We can get AAA shooters on anything, but games like SMW, Mario 64, Ocarina, yadda, are one of a kind.

Nintendo for games / Sony for hardware

nintendo once was.
But now the market has changed and in my opinion sony is the most essential

Oeps, that's a little mistake.. Sorry!

Nintendo

Both MS and Sony can be replaced

If Nintendo stopped making Wii U's. Would anyone notice?

That's like if the same question was asked of handheld gaming, I answered Sony. Nintendo is as essential to console gaming as Sony is to handheld gaming.

Nintendo.