From a historical perspective, a claim like this - that the technology is "500 years beyond our own" - is totally meaningless. It has no analytical value whatsoever. Technological development cannot be measured in years. It is the product of an enormous range of contingent factors, many of which cannot be quantified or predicted at all, like the perceived necessity of a technology, or the relative status of innovation in society. New technology doesn't simply appear when some cosmic clock declares that the time has come. It also doesn't follow some kind of linear progression from stone tools to UFO tech, with every society sitting somewhere on that line and progressing at a certain speed. This is just not a historical way of thinking. It has no bearing on reality.

When someone claims that the tech seen in these videos is "500 years beyond our own," what they probably mean is that if they were to make a rough estimate of the problems that would need to be solved and the resources currently available in the US to solve those problems, they would say it would take about 500 years. That is a more practical and therefore arguably historical way to read a claim like this. But when we rephrase it like this, we immediately see how much the estimate leans on human factors: how seriously a society is willing to focus on, and invest in, the attainment of one particular goal. Even if we assume that the claim that it would take 500 years is literally true under present conditions, it would have to be adjusted year on year, as the availability of resources and the prestige of the work changes, and as our understanding of the problem itself changes with further research. This notion is therefore wildly unstable. To name just one thing, if climate change progresses at the currently estimated rate, then it would actually take us thousands or even tens of thousands of years to unpack the problem of UFO flight, because it will become less and less of a priority to do so.

But the same understanding of technological change as a process driven by humans for concrete reasons also works the other way. Things aren't randomly invented. Technological development is always an incremental process in which each step is predictable to those who know what technology is currently being sought. More importantly, military technology rarely forces instant and total changes to the military power balance, because armies are enormous organisations which rely on policy issued by even more enormous organisations, and the way they do things is affected by social and political attitudes, logistical possibilities, doctrine, training, and experience. In other words, it will very rarely happen that any single invention is perceived as a "massive leap in military power" that so completely supersedes anything that preceded it that it seems to belong to a distant technological future.

Most examples of such perceived technological leaps actually don't turn out to be such enormities when you look at their context. The dreadnought battleship or the atomic bomb only made it easier to do things that military forces were already doing. As doctrines shifted and the needs of war put pressure on military engineers, both of these things were fairly obviously going to happen. Similarly, the colonial wars of the Early Modern period rarely involved a confrontation between totally different technological systems; the Maori who faced the British in the New Zealand Wars fought with double-barreled muskets and their earthwork fortifications were as sophisticated as anything you'd have found in Europe at the time. Even where the disparity was greater, the factors of logistics and numbers makes it unlikely that the technology itself made the difference that explains European success.

To put it simply, the kind of leap in military power that you're referring to doesn't really exist outside the minds of people who will say things like "this UFO tech is 500 years beyond our own." It is not a historical claim, but one that grows out of our modern cultural obsession with technological "progress" and with the idea that such "progress" made Europeans more "advanced" than the rest of the world. I would have to leave it to my colleagues to address the imperialism and racism inherent in this worldview, but suffice it to say that this is not really how science or technology work, and that, almost by definition, giant leaps in military technology cannot happen. A narrative of giant leaps will invariably be glossing over a ton of prior steps and important context in order to preserve the picture of the scientific genius who is lightyears "ahead" of their peers.