How could it have been a major haplogroup among those peoples if I2a-Slavic was a haplogroup present in only one single man who lived 300 BC(as TMRCA tells us)? Illyrians and Thracians were maybe hundreds of thousands at the time that I2a-Slavic was just one little person.
First and foremost - nomenclature: I2a-Slavic and I2a-Dinaric do not mean a thing in the current discussion, it's totally bogus to understand whether you mean I-CTS10228 (formed 5098 YBP; TMRCA 2213 YBP; i.e. 3148-263 BCE) or I-S17250 (formed 2341 YBP; TMRCA 1722 YBP; i.e. 391 BCE-228 CE).
You do not take into account that Illyrians and Thracians were widespread and that at the time of continuous mention of Illyrian tribes since c. 4th century BCE, they were at their downfall. They were not numerous, especially Illyrian tribes. They fought Macedonian, Celtic, Roman and inner Illyrians wars. Afterward happened Hunnic and Gothic invasion and plunder, their number diminished, and you think that a century after century of war and death this "slave" could not be someone from the wider Balkan area? You think that there existed some kind of impassable borders, that people from Illyrian times did not migrate to the north? That during Hunnic invasion some "slaves" could not arrive from Balkan to for e.g. Poland, and hence so many percentages in these parts of Europe?
If you see the countries with more I or I2a haplogroup individuals committed more crimes against people. If you notice the two countries that have killed more people in Europe are Germany and Serbia... On the other hand because Thracian lacked I2a they were soft people because they did not have I2a. So were Illyrians...
This is the most racistic and stereotypical nonsense I read these days. Where are moderators now? Also calling Thracian and Illyrians as soft is showing a total lack of understanding about their history and warfare.
The sad fact is that you're all so alike, and no, none of you are "pure" Slavs.
The image is about autosomal DNA, and as such it does not prove that haplogroup we discuss is Slavic at all.
TMRCA simply means Time to Most Recent Common Ancestor of a subclade or a mutation, and not when the actual migration happened. Therefore the migrations can only happen after the TMRCA lived. In this case after ~100 AD, when the Slavs were already expanding.
TMRCA of I-CTS10228 (263 BCE) is the average number of its subclade formation age, hence I-S17250 has a different formation age compared to TMRCA (391 BCE). From this is clear that I-CTS10228 formation age and TMRCA, as well I-S17250 TMRCA can not be used as an argument for Slavic migration. Even 200 years after I-S17250 TMRCA (228 CE) we are not talking about Slavic migration, yet Hunnic-Gothic invasion throught Eastern Europe, and as such it can be both an argument for indigenous Illyrian&Thracian or Slavic theory. If we take into account all formation ages and TMRCA of these two haplogroups, including formation age of I-CTS10228 (3148 BCE), then Slavic theory (ethnogenesis and migration) clearly can not be unilaterally and empirically supported with these numbers.
The ancestral clade of I-CTS10228 (I2a-Slavic) is in Poland in I-CTS4002*...
I am literally stunned with people's logic - if ancestral clade (moreover with only one sample!) was found somewhere in contemporary population it does not mean it was there in the ancient time period.