Yeah, the F-bomb getting the headlines for that episode says something about our sensibilities, doesn't it? Violence and sex = okay. A playful F-bomb = utterly unacceptable.
Hmmm. While I would prefer the violence and gore was toned down to family-viewing levels, Kilngons and their violent proclivities are
fantasy, they don't exist and none of it actually happened, and even so their actions are clearly painted as Bad Things done by Bad Guys. Swearing OTOH is a real thing that my kids are likely to do, that takes place between two human characters, including our cute bumbling Starfleet cadet character, and it's framed here as funny.
You can surely see the difference, from a parental PoV.
I love creative swearing, Deadwood is probably my favourite non-SF TV show of all time, but Star Trek is a show we have always watched as a family, just as it was tea-time viewing for me as a kid. It definitely
wouldn't have been if Bones' catchphrase had been "Fuck it Jim, I'm a Doctor, not a c*nt". I'm sure there were more examples, but in the entire 50 years of the franchise I can recall one 'bastard' (well repeated twice) and one 'shit', and I didn't care for the latter at all. Swearing adds realism to characters' speech patterns, but there's no need for it, and precious little precedent, in a far-future setting like Trek.
EDIT: Just watched Joe's links - forgot about the Merde!