Asking people to "taboo [X word]" is bad form, unless you already know that the other person is sufficiently (i.e. very) steeped in LW culture to know what our specific corner of internet culture means by "taboo".

Without context, such a request to taboo a word sounds like you are asking the other person to never use that word, to cleanse it from their vocabulary, to go through the rest of their life with that word permanently off-limits. That's a very high, and quite rude, ask to make of someone. While that's of course not what we mean by "taboo", I have seen requests to taboo made where it's not clear that the other person knows what we mean by taboo, which means it's quite likely the receiving party interpreted the request as being much ruder than was meant.

Instead of saying "Taboo [X word]", instead say "could you please say what you just said without using [X word]?" - it conveys the same request, without creating the potential to be misunderstood to be making a rude and overreaching request.