I'm certain Final Fantasy started on Nintendo
They did. There was a big hubabaloo about it back in the day when Nintendo fans got upset about FF7 switching to PS1, but a ruddy good job they did. I don't think Final Fantasy would have succeeded in that generation if they hadn't. 6 was a masterpiece that was always going to be difficult to match; staying on outdated hardware (no judging, I do like the N64 and the games made for it were good, but it was objectively outdated hardware) would have shot themselves in the foot. Squaresoft made the right choice jumping ship...
Alas, Square-Enix would then give us the misery that was X-2, an entire trilogy based on XIII, and really dragged their heels with the VII remake, to the point that even if it wasn't the case, it feels like an emergency "oh crap, after XIII (trilogy) and XV, we need to do something that can't fail us!" And I'm saying that as someone who mostly likes Remake and Rebirth, some choices notwithstanding.
That was the big console war back in the day and their back-and-forth elevated the product.
And there is the number one reason why monopolies are bad, and why I will always be in favour of even companies I don't care for to still be allowed to try and have a redemption arc. Competition breeds innovation, while the lack results in stagnation. I was never big on Nintendo as a kid, my parents got me a Sega Megadrive (or Genesis for those across the pond), and then a PS1 instead of an N64. And I wouldn't change that if I could. I don't care for XBox... but that mostly stems from how these days, there are so few console exclusives that the latest generation of consoles doesn't actually mean anything. So that's more modern XBox, not XBox OG/360. And also applies to the PS5, but I actually got that specifically for FF7 Remake (and Rebirth)... when then a year later it was revealed it was only a timed exclusive... AAAARGH!
I'm not kidding... I would have not bothered with the PS5 and just waited to get them on Steam if they'd just told us that they were going to be timed exclusive and not
exclusive exclusive.
So... I suppose that my vote goes to Microsoft XBox simply because they are the youngest console brand... the history of the other three means that it comes down to triage. Sorry XBox, but my childhood videogame history beats Halo.