Have PO made a proposal for a blanket retail tax?
Nope, but the latest PiS nonsense is that they'll have an 'amended' plan in place by the end of the month. The European Commission is already making it crystal clear that any tax that appears to target foreign retailers will be unlawful, and the whole thing is quite likely to be dropped.
Hello to higher VAT as a consequence.
ft.com/fastft/2016/02/10/polands-retail-tax-may-wipe-out-tescos-polish-earnings-moodys/
Poland's new proposed tax on supermarkets is credit negative for major international retailers operating in the country, Moody's has warned, estimating that the levy could wipe out Tesco and Carrefour's entire operating profit from their Polish businesses.
As mentioned earlier, margins are tiny in retail. If Tesco and Carrefour can no longer make a profit in Poland, they'll leave - and many jobs will be lost. Polish retailers won't replace them, because they simply don't have the supply chains or finance needed.