only rural, and uneducated people voted/support PIS.
pretty much the case now, i don't think you were in Poland so you maybe don't remember the parliamentary campaign.... PiS ran on a platform of not being.... PiS. That is Kaczyński and Macierewicz were kept out of public and did no campaigning and PiS was marketing itself as a changed party - of normal non-scary Christian Democrats - which would certainly make sense. Szydło suggested that JK and AM would play no role in a second PiS government and many people believed her.
The second results were announced JK all but shoved Szydło off stage and his very first agenda was to attack the constitution and to try to turn the judicial system into his own personal rubber stamp factory.
I knew people that voted for PiS and within a week were completely disillusioned and felt betrayed.
That's why educated people turned away from the party - they didn't like feeling fooled.
Had PiS acted like a normal Christian Democrat party working within the existing system and not squandering public monies on crazy Smolensk stuff and a completely unnecessary 'reform' of the education system and not tried to cut down Białowieża...then they might have more educated support.