In the past three years I've repaired two washing machines whose main PCBs were not coated (neither were they broken, the washaing machines were defective elsewhere). One was a Beko, so more on the cheap side, and one was some Aldi-branded Italian make I haven't heard of before. I think the name was Whirlpool. It was extremely cheap and the connectors burned after a few years of use, taking the main PCB down with them. But even the replacement part was not coated.

I think only the more upscale or expensive ones are coated for longevity.