My car key fob has been through the washing machine multiple times without harm, if anything it was better as it was clean! It’s 9 years old, lives in my pack when riding so gets soaked and filthy regularly and has never failed to work. Still on the original battery too.
My Garmin 800 went through the washing machine a few times, never any worse for wear when it was stolen in Chatel. The replacement 810 hasn’t been through a wash yet though.
Put a 2S Lipo from one of my RC cars through the machine once, didn’t burst into flames but was much less powerful afterwards.
Thinking about it I don’t think I’ve killed anything via a wash cycle. Oh no, I forgot. Multiple pairs of Sealskinz socks have gone all crinkly and useless after being washed at 40 degrees.