Nothing wrong with using the old kill yourself. I think it becomes an issue when people say this constantly to someone who is a regular target of harassment and bullying though.
So to contextualise (i don't even know if this word is appropriate but it sounds smart) some of the people I work with, I regularly suggest that they end their life especially when they greatly **** something that then requires un-****ing. I will also tell them that I am off to end my own life when I **** something. Which to me is perfectly fine. We all have a laugh, I hit them with a ruler, they punch me in the kidneys, we all go to the pub. The end.
What I would not do is berate someone for ****ing things up to the point that they display signs of depression and then start suggesting that they are no good for anything and they should just ****ing commit suicide.
I think the hard focus on effects of bullying etc over past maybe 10-15 years although doing really good things for society has also worked to lower peoples tolerance for verbal insults. Or has planted the seed of thought that anything that you perceive as offensive is a criminal infringement on them. Don't confuse this with me condoning bullying because that is a scummy thing that has cost people their lives. Maybe its just Newton's third law at play.
What I don't get is when I accidentally stumble across one of those videos of United States universities where people are having a public sook about something they perceive to be verbally insulting, but to make their point they are screaming in someones face about it. As far as I am concerned, tone is more offensive than words. I would much rather have someone call me a ****ing piece of **** with a civil tone then for them to get in my face and scream its muffin time. Just seems like the biggest load of contradictory ****.
If you have a problem at work where someone has a cry because you say something mean to them (as long as its not ****ing extreme what you said), its quite simple just don't ever say anything mean to them ever again, don't joke with them or engage them with anything other than a formal tongue. Sit and wait, the minute they come out with a racist, sexist, homophobic, or personal insult jump on it, and they will eventually do it. Then have it dealt with via the companies complaint system. Every time they do it make a complaint. Its not being spiteful its just holding them to the standard of formality that they have set. They made the bed, now they have to sleep in it. It does not mean your a *****, chances are you wont even give a **** about what they said but if they hold everyone around them to some godly formal verbal standard, they too must live by it.
tl;dr people are *****es. be a ****. don't bully, there is a line. Be spiteful.