This is good theory, but it's not been aligned with the 10D string universe, which is the one the video tries to talk about. I personally think there are ways to reconcile the "astral realm" with the curled dimensions, but it's best to talk about the two topics separately until we can draw isomorphisms between them.

If the universe were conceived as a single particle that travels every path forward and backward in time that we conceive of as being many particles, that particle could be conceived of as experiencing all realities. Astrally, if there were many "universes" that had power of connection, such that there might be many Americas each with a slightly different history and many alternatives, then their connection would still permit traversal by this single-experience particle; but of course each individual version of you would be a different person, and there may in fact be such blur among people that you could keep making modifications of "you" until you arrived at a different person extant in this universe. There would be no species of "you" and species of "other", it would all be a spectrum of humanity on which you are a data point. (Of course I don't think those possibilities would be strictly infinite in any direction, I think they would have certain limits like the spatiotemporal dimensions, such that there would be a more manageable number of them like a googolplex.) If then we could jump universes we would still face the problem that each alternate universe still has its own problems (grass not greener). Ideally instead of a universe with "rich you", you'd prefer a universe with a void in it that could be suddenly occupied profitably by the current you that has certain experience that you could exploit in the new universe.

The participation in the all might increase in the future but is still limited by individuality now, and so we should seek in the now the best means of hoping to participate in the all in the ways the laws of physics permit.

But, oddly enough, we already have enough space in these four dimensions to make more local jumps (similar to inter-universe jumps) to improve our lot, and we are still subject to time and chance despite our best attempts, and subject to the equal attempts by others to take advantage of these opportunities. Others might jump into our universe to their advantage too, against our ignorance. So adding universes doesn't help much!

Dreams are very important, but we always wake up in this same "reality", not some other. This suggests that what we are contacting is not "alternate" but "supplemental" to this universe. The dream or astral realm informs, but does not share the physical uniqueness of, these dimensions. This is why I refer to that realm as uncurling the additional dimensions, which in astral language is called "opening" (e.g. the heavens). Usually our timeline experiences one or the other, but sometimes both the dream and the reality at once. Whether the process is possibility navigation or creative choice doesn't matter, we're still stuck with the one timeline. The only transcendence for this reality that I see is to become so broadly simultaneously cognizant of such a range of the universe that one transcends the lightcone (perhaps, one's life "flashing before one's eyes"); and yet this is still a linear experience, just as a dream is. I have a philosophical proof that if it were possible to transcend linear experience the possibility could never be known in advance of its being achieved by the one experiencing it.

So it's important to use the scifi to imagine and test boundaries; and when we return to reality we are free to seek how to implement these imaginations. It seems to me that some imaginations just don't work but most can be refined until they get closer to science. So I encourage the continuing exploration, while I lay out my principles for good and worse directions to explore.