So, the conclusion to draw is that they are targeting families living in bigger cities where rents are 2 to 3 grand per month, making the PIS plan rate of a grand a good deal.
The proof will be in what actually gets constructed. They've already said that potential renters should not expect to get modern, high quality apartments but rather functional ones - which means prefabricated, modular and with very little green space. If they're not located near city centres, near good roads or near good public transport connections, then they'll be even more undesirable.
Can't speak for all cities, but I'm wondering where this state-owned land actually is. There's a lot in rural areas, but for instance - in Poznań and Wrocław, I can't think of any large areas that are state-owned and not city-owned, except military land to the north.