That video looks like junk.
First, to describe a universe containing every quantum possibility, you need
infinite dimensions. Not just 5.
Infinite. Quantum superimposition gets interprited as interaction between non-orthogonal parts of this infinite dimensional space, and Quantum collapse as a rotation of two parts into being orthogonal to each other.
They cop out and call this "the 5th dimension".
Second, the mobius strip example -- which works perfectly fine if you use a simple loop. The use of the mobius strip adds nothing to the description. There are uses for the mobius strip in dimensional analogy, but that wasn't one of them. So they lose points for "extra confusion for no reason".
It continues being cheesy from then on out, and more addle-brained.
Most practically, it ignores the most common interpritation of String Theory -- which is that the higher order space-like dimensions are tightly twisted up -- alot of the gobbly gook he is talking about gets thrown out. While the 3rd dimension can be viewed as a bunch of slices of flatlands, the one we are in isn't such a bunch of slices of a flatland universe with any kind of reasonable flatland "laws of physics".
The ant on the wire analogy explains the situation much better.
Take a line. That's a 1 dimensional structure.
But if you took a cable, and
looked at it from far enough away, it would look like a line. From far enough away, your position on the line would be described by only your position ALONG the line.
If you zoom in, the diameter of the cable starts to matter. To an ant, the cable is two-dimensional: it has a length, and a circumphrence. To describe the relative position of two ants on the line at a scale the ants care about, you need both the position ALONG the line, and where AROUND the line you are.
The top String theories is that the 6 "missing" spacial dimensions are very much like that cable. They are tiny, curled up dimensions.
...
String Theory is a mathematical model that, as far as we can tell, is
consistent with the physical world. As yet it has not made any verifiable
predictions that have panned out that where not also predicted by much simpler theories.
Attempts to verify some of the most interesting predictions of string theory which are not predicted by "simpler" models have, as yet, failed to pan out.
What String Theory brought forward was a way to deal with the indeterminate location of Q-M and mathematical singularities that fall out of particle theory. By treating fundamental building blocks not as 0 dimensional points, but at 1 dimensional strings, alot of singularities in the math go away.
One thing that makes String Theory "not even wrong" is that String Threory can describe
way way more universes than one. So it doesn't make predictions as much as admit possibilities. And we lack the ability to say that String Theory rules out a particular possibility.
String Theory is a theoretical framework which physisics are playing with. It has some wonderful philosophical advantages over some of the competing frameworks, and is currently in vogue. However, it has yet to pass the test of making and standing behind a surprising prediction.
They are attempting to test some of the surprising possibilities put forward by string theory, but they haven't succeeded yet.