What about the Bell Beakers? Surely that is a shining example of pots are not people. There was a lot of trade throughout the world in the BA, but now we see that places like Anatolia were genetically impregnable until the IA
Bell Beakers were considered by the "pots not people" crowd just a "social happening" and "trade network phenomenon". What is the reality? In some regions they eliminated within their sphere nearly 95 % of the local male lineages and replaced them. The autosomal replacement varies, but is in one of the highest ballparks every recorded in prehistory.
Yes, they did adopt elements into their package, before swarming out, largely. But here too: Where you got the whole cultural package, they did replace, with a few exceptions.
And I highly doubt the conclusion of Reich, its simply impossible. Even if the PIE would have been sitting somewhere around the Caucausus, that there was no penetration of Anatolia before the Iron Age, nothing recognisable at all, is simply not possible. I can only attribute it, if he presents any sort of data in that direction, as bad sampling strategy.
I'm particularly curious about Cernavoda into Troy. Whether they tested those groups and what's the outcome. If they didn't test it, that's like talking about "Yamnaya expansion" while ignoring Sredny Stog and the Lower Don cultural centre in the period before. Its just missing the point, either deliberately or by accident.
I find it kind of silly to think ancient people cared so much about pottery and or even where their language came from even just 1000 years before them. These things only seem important because of the massive blank spots of what we know of in those times. Imho
Take G?va pottery as an example, it was ideologically, religiously loaded. Being connected with a specific ideology, whole package and religious motif.
People did keep specific pottery traditions with a strict borderline between complexes for hundreds years. And so far, in many such cases, if there was as strict border in the cultural package, the easiest to define aspect is pottery, then there was also a strict genetic borderline. We deal with different ethnicities.
That some people were as delusational as to say Channelled Ware appeared as a matter of "trade and contacts", even for areas in which there was never such kind of pottery before, yet it appars after all the settlements in the valley being burnt down and the local survivors fled ot the hills, is just idiotic. Even more so, if its not just the pots which were fine ware, black burnished, with channelling and knobs, black outside, red inside, but specific swords (Naue II category type Reutlingen), spearheads (like the casted flame shaped spearheads), molds, jewelry including fibulae (knobs), ritual pits, cremation burials in urns and scattered ashes, ritual hoards, first iron working etc., etc.
But of course, all those things which were extremely rare to non-existent appear after in some regions whole clusters of villages were burnt to the ground and the locals fled to the hills, that's just a (un-) lucky coincidence! Has nothing to do with migration, or that the groups to the South started to cross the Mediterranean as the Sea People, or the Illyrians moved to Southern Italy, because of the pressure from the North. That's all something people have "imagined".
I totally get that a culture or people could adopt foreign influences, but you know what's the difference: If local people just adopt a new style, it shows, it just shows. Because they do it in their very own way, based on the preceding traditions and they don't give up on all they made before, nor do they take up the whole package the foreigners brought in.
That's e.g. in Pre-G?va Lapus I the case. They still used earlier incision and broom stroke techniques which were old in the region, which other branches of G?va did not to the same extent. If you see something like that, you can say that its a local uptake or development.
But then again. For what I'm debating here, things are way different: We have the evidence for invasions and we have whole packages appearing and replacing local ones. Either fully or partly, with a speed (within one generation) which never happens without a large scale migration.
The funniest part is, that the evidence for Channelled Ware people's migration is better, with way more density of finds, than that for the migration of Celts in many areas, and of Bell Beakers and Corded Ware in particular. Because of the latter, you rarely have scenes of slaughter and a destruction horizon. They just appear, but the transition is missing. In this case that's true as well, for many areas, but in many others, because of the density of settling in that period and the finds made, we can actually see that they besieged and destroyed fortresses and settlements.