Where Did Earth Get Its Oceans? Maybe It Made Them Itself

Correct, and we can demonstrate this via various gem-bearing and REE-bearing pegmatites which almost universally contain magmatic-sourced water trapped within them.

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I thought it was ai generated lol

1) Land has more diverse and rapidly changing environments, creating generalists, creating advanced intelligence

2) Civilization requires hands, but in water fins and flippers are more useful

3) Sure, it could have worked out differently, but here we are

That's one theory, yes. Cooking food (with fire) makes more calories available, meaning less hunting required to support more individuals, and/or freeing up more time and calories for thinking. This allowed us to evolve bigger and more complex brains.

While it's not a given that fire is a hard prerequisite for an industrial civilization, it certainly accelerated our technological development. Fact of the matter is, we know of exactly one civilization, which is not enough to draw any conclusions. There's no real reason we know of that aquatic species cannot evolve into a technological civilization, we just haven't seen it happen. Fact is we don't really know how an intelligent technological species evolves. We only have guesses from our own history.

Brains are resource hungry, especially oxygen hungry. Earth's air is orders of magnitude richer in oxygen molecules than its water. This likely made it easier for intelligence to develop on land. It's worth noting that the smartest aquatic animals are air breathing mammals that spent much of their evolutionary history on land before returning to water.

Interesting to think what could be if cephalopods raised their young instead of leaving them to completely fend for themselves. It would start intergenerational knowledge transfer, i.e. culture. Maybe selection pressure then trends towards group cooperation instead of going it solo.

I still think there would be huge barriers to "civilization" as I think you mean? (Do any of the apes have "civilization"?).

Physically manipulating objects is a lot harder underwater, even if you somehow evolve fine motor control despite not having any real use for it. So that severely limits what an intelligent aquatic species could actually do with that intelligence. Aside from fire you're missing the wheel, a writing system and many other things.

One hypothesis is that the brain began too look (and eventually plan) farther ahead with land animals, because you have a much farther view in air than in water. On land there is more evolutionary pressure to change one’s behavior regarding animals farther away that you see and that can see you, to predict their behavior and plan one’s own behavior within a larger time horizon.

You're talking about a thing that happened for 1 species for such a small period of Earth's history to be just a blip. There's not enough data to draw a conclusion here.

Humans are one of a handful species equipped to change their immediate environment to suit their needs, across virtually every environment, and introduce stability.

Beyond that…

Being able to have down time seems like a prerequisite to creating. civilization.

Also, having both the intelligence and desire to seem and recognize ways to improve—even if not strictly necessary—via tools to free up even more time also seems to be a requirement.

And having a system to reliably and in-scale transmit this knowledge is the final ingredient.

So some baseline stability, down-time, intelligence, reliable knowledge transmission, tool-use for the above, and active willingness to improve all of the above all seem like necessary ingredients.