Notwithstanding the title, the video goes beyond the ideas from Oswald Spengler, but also draws in ideas advanced by Sir John Glub, Peter Turchin, Joseph Tainter, and Arnold Toynbee. Of course, some, such as Glub, were speaking merely of the collapse of empires while Spengler spoke of civilizations, and Turchin and Tainter's works could be applicable to either.
The point is that we are in the late fall or winter of Western Civilization and in a period of decline of the United States, nearing a critical juncture per Tainter and Turchin. I suspect that Turchin would actually point to the rise of the DSA as evidence of a revolt in the process or having occurred among the elites, pushed along by the BLM movement and accompanying riots. But I doubt it is the end of the process because it has not resolved the underlying issues of income disparity and the wealth pump, merely shuffled some of the old guard off the stage in favor of a younger generation of elites. In fact, the DSA cannot resolve this issue because the DSA supports policies that benefit the wealth pump. And behind it all is Turchin's theory of collapse based on a concept that complexity will reach a point where it is simply unaffordable.
I would note that it is possible for a civilization to transform and revitalize, which is something that Carroll Quigley briefly discussed in his book, Tragedy and Hope. This happened to Europe after the discovery of the New World--part of a larger transformation into world trade and expansion. It could happen again, most likely based around space exploration, development, and colonization. Otherwise, I fear that the future will be one similar to the Bronze Age collapse with a multitude of countries experiencing collapse simultaneously or nearly simultaneously.
VIDEO: "Every Civilization Dies the Same Stupid Way — Spengler Predicted Ours"
Mindplicit (27 min.)