Unlike you, I have some modest knowledge about this topic, as I’ve previously read other works on the subject, including of course what was written by Eran Elhaik. You can find that scientific paper on Jstor, I hope you at least know what it is, since your “knowledge” reaches as far as I can tell only to Wikipedia, the mother of all “knowledge”.
Also, I hope you at least noticed that literally all the participants in that scientific study you refer to are Ashkenazi Israelis or Ashkenazi Jews from Eastern Europe, and that their bias and desire to prove at any cost what they really want to be true is simply eye-popping from every page of what is written there.
Anyhow, I will try to explain to you some basic things, although I am not sure that you are capable of understanding. The situation is essentially very simple. So, with this type of genetic testing, the most important thing is to determine the haplogroup, which is a genetic population group of people who share a common ancestor. In general, practically the entire population of all ancient peoples was always composed of members of only one haplogroup, because the ancient peoples arose from corresponding prehistoric tribes where almost all members shared the same ancestors. I think this should be clear to you, unless you slept in class at school. For example, Slavs and all their descendants to this day have the R1a haplogroup, where according to the corresponding subclade it can be concluded which type of Slavs and their descendants are in question.
Also, and what is most important, by the number of mutations it can be determined when a branch or subclade separated from the main population and migrated somewhere, or who came from which direction and approximately when. That’s because each of us shares a completely identical genetic imprint with our fathers, grandfathers and great-grandfathers, where one mutation of that genetic code only appears every few hundred years.
Everything that applies to the Slavs also applies to the Celts, Germans, Arabs, of course, and should also apply to the descendants of the ancient Jews. For example, over 50% of today’s Russians and over 60% of today’s Poles as descendants of Slavs have haplogroup R1a, while over 80% of today’s Irish have haplogroup R1b as descendants of Celts.
However, if you look at the results of genetic tests of Ashkenazi Jews, it is immediately noticeable that there is no dominant haplogroup, which inevitably indicates that it is a diverse mixture of various peoples, and that the origin of almost every one of those haplogroups and/or populations that today share the same genetic heritage or around the Caucasus or in Europe or in North Africa. The writers of that study you refer to explained that diversity in an almost ingenious way, such that, for example, the inhabitants of Cyprus are of equally diverse origin, with some similar haplogroups included in that mixture. Yes, but unlike the Ashkenazi Jews, no one in Cyprus thinks that they belong to the chosen people, nor do they go to Palestine to colonize there…