And I agree with what you are saying. But I'm coming from it from a practical point of view. What we do know is that Druids are Indo-Europeans, like the Germanic peoples etc. We also know that there is a common thread among all shamanism practices, the world over, but especially among Indo-Europeans. The practices had common themes.
We also have some details from the Greco-Roman, and we have an oral tradition that came down into Christian times. Let's not forget the Norse, who did leave some records, even if they are remnants of an older oral tradition. Nevertheless, Iceland kept its traditions intact well into the Middle Ages.
The traditions evolve. They have evolved in Greece, India, China, as well as Scandinavia, which apparently transformed existing petroglyph symbols into runes inspired by the Latin alphabet, and it worked great for them. As I am not a scholar who wants to take a snapshot of every detail of practice, I can take the term Neo-Druid as an extrapolation of both available data and esoteric understanding- and there is enough to do so, in my opinion, I would deem the practices sufficient to be at the very least a legitimate inheritor of the original.
Otherwise, any tradition would be halted because the march of time leaves nothing unscathed. Greeks and Romans did leave records, but just how many of those records have been lost (Library of Alexandria going up in flames more than once, for example)? So the Greek mystery tradition doesn't have all that much data because of the secrecy, but the few accounts we do have allowed some extrapolation.
Another aspect is, now that I think about it. Because OP asked and stated that modern druids are nothing like the original ones, because of the lack of knowledge and records that survived.
But aren't modern britains even like the original bretons?
Just 500 years ago the english language in britain was completely different to today. And 1000 years back it was more similar to west German dialects. And during the times of Arthur it was a different language alltogether. Yet they still call themselves "Britains" and act like it and call back to their heritage.
Perhaps modern druids can exist and while they may not be like the original druids, they try to carry on the torch to the best of their abilities. Perhaps this is what counts.
Like the people who build stonehenge knew exactly what it was supposed to do. And today? No one can say for certain. They can't even say how the stones were cut/ molten and how it was build. And stonehenge was pre Arthurian too.
Or the pyramids. They have been built and those that did it knew what it was supposed to do and use it. Then the dynasties came, put their dead kings in there and suddenly it was a tomb. Yet ancient egyptian records state that they themselves do not know what the pyramids are supposed to do. Some 6k year old stone inscription state that they try to restore parts of something broken on the pyramid and how their repairs looked so shit and inadequate compared to the original parts and they say "How did they even built this if we can't even repair them?" And the repairs they did disintegrated faster than the original structure.
Or more modern. Roman concrete. We have aqueducts and water systems here in europe that have been in place since the romans. They work better than our modern stuff and it just doesn't disintegrate. The water pipeline to vienna is the same the romans build for example. Or in spain, a random "wall" the romans build turned out to be a barrier for flooding. It happened a few weeks ago, and that barrier perfectly saved a city. People didn't even thought that it was meant as a flooding barrier. As those floods only appear every 500 years perhaps. It was such a fringe use for them.
Or greek fire. Yes it might be Napalm but still.
Lost technology. Or imagine a blacksmith in Venezia that made nails for roman warships. Nails that never rust. No one today know how they did it. Because the technology "became obsolete". Since now we weld things together or cast them.
Likewise it's with other technologies. And then they dig up little gimmicks and tools in Iraq from sumer times and they simply can not fathdom what it was or supposed to do. A battery? A lightbulb?
Likewise its with tradition and spiritual practices. Evola stated that humanity is not evolving, but continually devolving. Forgetting everything.
People that lived on atlantis 13.000 years ago might have known about things we dont even assume.
Like take radioactivity for example. This exists and existed long before Curie "discovered" it. It existed during roman times, but people couldn't imagine this.
Or radiowaves. Do you even know how cell towers function? It is the most insane stuff you can think about. Compared to remote viewing, it seems that remote viewing is more "scientifically sound" than millions of charged air particles carrying what I just typed out on my phone to whoever wants to read it. Imagine this. What I just wrote traveled to space and back in the matter of a split second. All through the air and vacuum. Carried by charged electrons. And somehow we have mcguffins that can translate those charged electrons to pixels on the screen.
And who knows people in 500 year might have forgotten how to do even this. It sounds ridiculous after all right? Sending modulated electricity through the entire earth. But not just once, millions of times in a second (thats what hertz is meaning) and not just that but 20 Million different ways. Since we have radio, TV, other comms, other people using phones. And they all do not interefere with each other. How peculiar. No one will belief you if you tried to explain it, yet it works.
