Why the double standard?
I think there's a big difference between the European Parliament and the Polish Parliament and in particular the program followed by PIS since they were elected. The European Parliament follows a system whereby legislation comes into being. Matters are properly debated before a vote is taken. In general research is carried out on various proposals and is presented to members of the European parliament, concerns are aired and addressed, individual nations conduct their own research etc. There is a good deal of discussion and when the Parliament rejects something, it's back to the drawing board and the proposals have to be re-hashed. That's not the case in Poland. Legislation to which PIS anticipates objection, is pushed through as private members' bills as opposed to government proposals.
Also, if you look at the scale of changes in all keys areas including fixing things like the education system which clearly weren't broken, that PIS has wrought in a very short space of time - well any person of intelligence can see that there is really no comparison.