Why did the Silesian voivodeship vote for PiS?

So I was recently on a trip to Poland (Silesia, to be specific) and I was struck by a lot of things. Firstly, when I was in Katowice I noticed fairly large amounts of people protesting the PiS government and generally seemed fairly left-wing. When I got to other cities, I didn’t notice anything of the sort. But the most interesting thing was to me that in the elections, PiS won the vote in Silesia. This surprises me greatly, as the Silesians have been a historical working class people, and with PiS’ general hard right narrative, I wonder why they won such a large percentage of votes in Silesia.