>>1280394This isn't quite the story. What actually happened is that when Poland was finally retiring their steam fleet in the '90s, a British tour operator and railfan managed to convince the rail authorities that if they'd keep some steam locomotives in action he could cover the extra costs compared to electric or diesel by making it a tourist attraction. The big moneymaker was a vacation package called the Wolsztyn Experience, where you spend several days to a week learning to drive a steam loco and then operating it in real revenue mainline service. This package still exists, but they think 2019 will sadly be the last year of it, as rising costs and aging trains and crews are making it unsustainable.
What this ISN'T is a heritage railway, though. This is still a real commercial mainline operation that just happens to operate several steam locomotives alongside their mostly electric and diesel fleet. That's a big part of the draw for tourists.