Please do not confuse non-Polish speaking players.
Nowhere in the interview we announced or confirmed new Polish Tech Tree.
We know that many Polish players are asking for a separate Polish tech tree. While we can't confirm any specific plans, let's just say that we are committed to finding a way to add all the important military vehicles that actually existed. As you can see, we found solutions for South Africa and Israel, so there may be a solution for Poland as well.
Edit.
Ok, I see you are talking on ANY nation:
Right after Israel, there will be a new nation in War Thunder and it will be a country with some pretty interesting and original vehicles, especially ground vehicles.
Sorry, that IGN Poland confused me a little.