>>17973753
The opposite is true. Slavic Y-DNA forms a major lineage in nearly all regions of Greece, with Thessaloniki being the only region where both Slavic Y-DNA form the primary lineages, but the author of the map chose to put E1b instead of I2a because it had a small 0.2% advantage over I2a.

>>17811118
Fun fact, the author of this map, Passa (a long-time contributor from Anthrogenica), had to put E1b instead of I2a for Thessaloniki because he didn't want the "Slavic effect" to be even more apparent, even though E1b and I2a have the same percentage. It's based on all studies and FTDNA results till 2016, the I2a in the mainland is in its entirety I2a1b-Din.