I believe you to be mistaken. The entire episode is about an accelerating earth. Einstein is talking about an accelerating earth, not "bendy space," in his argument to the Newtonians. He didn't come up with bendy space until seven years later.
This is literally what it says in the video. From the transcript:
Isaac Newton said that an Apple falls because a gravitational force accelerates it toward the ground, but what if it's really the ground accelerating up to meet the Apple?
Suppose I drop an apple according to Isaac Newton the ground can be considered at rest Earth applies a gravitational force to the Apple and that force causes the Apple to accelerate downward but according to Einstein there's no such thing as a gravitational force instead it's more appropriate to think of the Apple as stationary and the ground along with everything on the ground as accelerating upward into the Apple.
Now what I just said sounds preposterous and maybe even moronic, but it's not sophistry. There's something substantive here, and today I'm going to clarify what exactly this point of view means why Einstein came to adopt it and how it planted the seeds for what would eventually become General Relativity.
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Now, in Newtonian physics this is just an accounting trick that has no broader significance. Really, Dustin's car is accelerating and this extra backwards gravity is fake, but Einstein asked: Hold on, what if the so-called real downward gravity from Earth is also fake? A side effect generated because Earth's surface is really accelerating upward.
Now, you know what Newton would say. He'd say “that's crazy” and would remind us that inertial frames are the standard for measuring true acceleration. So you can only say earth is really accelerating upward if you can identify an inertial frame relative to which Earth's surface accelerates upward and there's obviously no inertial frame like that.
“Well, not so fast” says Einstein, maybe there is.
What about a frame that's in freefall? Think about it. If I put you in a box and drop you off a cliff, in the frame of the box everything just float weightless. The falling frame of the box behaves just like a stationary inertial frame that's way out in intergalactic space where there's no gravity. So why can't the box's frame be inertial as well?
Because, Newton says, that falling frame can't be inertial. It's really accelerating downward at 9.8 m/s^2. The interior just seems like zero-g because the downward acceleration acts like a fake extra upward gravitational field that, from the perspective of the box, just happens to exactly cancel the real downward gravitational field of Earth.
By coincidence.
Really Newton? Really?
Einstein says: Look buddy, I'm just following your rules. You established the test for what an inertial frame is. Release a object and it stays put. Stationary frames in intergalactic space passed that test, but freely falling frames here on earth also pass that test if your so-called gravity is fictitious.
More to the point, Newton, if you're inside the box there's no way for you to know that you're not in intergalactic space. This inability to distinguish free fall from lack of gravity has a name by the way. Einstein called it the Equivalence Principle. And if you buy it then maybe the falling frames really are inertial. If so, then it's the falling frames that establish the standard of non acceleration, in which case it's really the ground that's accelerating upward and what we've always been calling a gravitational force is an artifact of being in an accelerated frame of reference.
It's not different from the weird backward jolt that you experience on the train that you know perfectly well isn't being caused by anything, so why are you insisting that the downward jolt we experience every day on earth has a physical origin? Maybe gravity, just like that backward jolt on the train, is an illusion. Doesn't that point of view seem simpler?
Now, Newton says: Nice try Einstein, but you forgot something. Earth is round. Down isn't really down, it's radially inward, and this creates two problems with thinking about freely falling frames as inertial, or thinking about gravity as an illusion.
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If, instead the world has non-eculidean and curved spacetime then straight lines and constant speed doesn't mean what you think it means. And it turns out that inertial frames in curved space time can basically do whatever you want. It took Einstein about seven years to realize that. But once he did, a beautiful model of the world emerged called General Relativity. One of the central precepts of General Relativity is that we inhabit curved space-time.
Einstein won the issue by calling gravity an illusion, and saying that an accelerating earth makes more sense. This is exactly what the narrator states. Do you know more about this than the author?
So no, the bendy space stuff wasn't dreamed up until later. Seven years later. This is what is literally stated. You are making a scenario up, imagining that Einstein was really using his bending space explanation all along and never thought of an accelerating earth or used that argument.
The story is in chronological order, indeed. The Equivalence Principal was developed long before General Relativity. You are trying your hardest to remove all references to an accelerating earth. This is factually incorrect to the content of the video.
Feel free to argue "The video is wrong!" and "The scientist is wrong" all you wish. This is what the video portrays and the counter argument of "well, he's wrong" is decidedly weak.
"Einstein won the issue by calling gravity an illusion, and saying that an accelerating earth makes more sense. This is exactly what the narrator states. Do you know more about this than the author?"
Quite possibly, but that is difficult to evaluate. I am only saying that I do not think
you understand what the author means.
Now that is quite a claim for me to make, so I better justify it with solid reasoning!
Gravity
is an illusion, according to Einstein. What Newton called a force, Einstein demonstrated is a geometrical consequence of space. But wait, how does a curved space manifest as an acceleration? Well, objects follow the most direct path through space, we call this a geodesic, and we quantify such paths using mathematical objects called metrics. Relative to an external observer, an object moving through curved space will bend. Since its direction is changing, we perceive this as an acceleration.
So you see, Einstein was not really confirming that the Earth is accelerating upwards, what he was saying is that the Earth resides in a curved space-time, by virtue of the fact that it has mass.
Presently, you are drawing a distinction between special relativity and general relativity. The Equivalence Principle belonging to the former. I recommend that you not do this, however, because SR states that it is not possible for an object to accelerate for very long. The reason is because the energy needed to maintain the acceleration approaches infinity. The reason why the Earth is in an accelerating frame, according to Newton now, is because it is
spinning. The reason why objects accelerate in the vicinity of Earth, according to Einstein, is because the mass of the Earth warps the space around it. This has nothing to do with SR at all, and it a GR concept.