It is an issue in Poland. Close to 30% of the population is at Sunday mass and even if priests were perfectly neutral (and they very much aren’t) simply people deciding “I’m already out, I might as well vote” does make an impact on the outcome. Every time liberals and socialists score an election win is after electorate mobilization that counters that.

BTW I agree that voting should happen on a statutory holiday, but it shouldn’t be one associated with a majority religion.