The game is rated a 12... and if there a children under that age watching the screen then meh, that's down to the parents/guardian. If a child of 12 has not heard the term testicles or semen by that age then I can see sex education being a complete shocker to them lol.
On a serious note, I don't think the OP has an issue with there being a filter in place that people can use if they so wish. It is just that the words it decides to put a "profanity" filter on are a bit random. Why filter testicles (plural) but not testicle (singular)? If you see the singular you still know that the person typing is talking about their nutsack.....