I also sometimes think about topics that would be inappropriate in an office environment (such as sex) and I censor myself by not saying what I am thinking. We even have an Internetism for that concept - NSFW.
None of this is new - we are expected to conduct ourselves appropriately for the current situation. It's just how society works.
I didn't even read the document in question, I just have a very hard time with people getting riled up about being "censored" at work. It's work, what exactly do you expect?