I've spent 8 years at Amazon and for the most part I enjoyed it (mostly AWS teams). Never ever I felt anything even remotely similar to what has been described in all those stories. Not sure if I just got lucky or it's not bad everywhere and people with bad experiences are just more vocal.
Never been to Japan, but from description its the same type of toilets they have in South Korea.
Yeah, feel much cleaner, I wonder how is it hard to get same setup in US