That's important point, we have one of the oldest society in Europe, many of +65yo people doesn't have access to Internet or even if they have that, they don't know how use this.
Some time ago I read somwhere that around 25% of our population doesn't have permanent internet access, we can believe that most of that people lives in small villages.
Then such people might doesn't know about existence of other political parties than PO, PiS and time to time mentioned Lewica as they only are watching TV and mainly TVP and can know their programm only from TV debates. As we all know "thanks" to this, PiS have always advantage in villages/small towns and among +65yo people and they still will vote for them because they are giving 500+ and 13/14 additional universal retirement, which PO didn't it during their leadership during 8 years.