However, I have a couple of rules:
1) Avoid swearing with clients/customers/investors, at least wait until a relationship is established and they signal they're okay with it.
2) Avoid swearing in written communication, e.g., in emails or commit messages – don't even really like seeing it in team-wide slack channels, though I do it occasionally.
I don't mind swearing personally, but I do think it can be rude or unprofessional. Part of it is just signaling that you understand business etiquette and how to be polite in that setting – i.e., "professional."
For example, if I'm interviewing someone who immediately starts dropping tons of f-bombs, I'm going to judge that negatively – not as a deal breaker but as a warning flag.
I guess it would be similar to how I'd react if somebody immediately launched into a diatribe about religion or politics (regardless of whether I sympathized with their view). Like swearing, they're fine in a conversation between acquaintances, but they can easily veer into offensive territory if you don't know the other person. If you don't understand or don't care that you might be offending someone, I would be concerned about your ability to communicate effectively.
I am a sysadmin, I frequently swear in the most vulgar and crass way. However I do not and will not tolerate 'bro' culture.
If you are acting like a cunt to my fellow worker, I will make your work life a fuck sight more testing.
Do not pick on my fellow man/women, for I shall haunt you like a wet fart.
Secondly its not proud of being an arsehole, its proud of standing up for people. No one bullies on my watch.
Observe.
Swearing is lazy. It adds nothing to sentences. No value.
Which version was clearer?
Caveat: swearing used strategically can be fucking beautiful.
Something being 'fucking lazy' might not add more than something being 'lazy', but something being 'fucked' is an altogether different use.