I am affraid I must respectfully disagree with you on this one Pugilist. Fatalities are one of the few worthwhile additions to come out of the lacklustre Age of War. I had always disliked how Conan Exiles was so lacking in gore and brutality against the backdrop of the savage and barbaric Hyborian Age, and the kill animations felt concurrently too soft and repetitive prior to their addition. Furthermore, the buffs they confer I find very helpful when slogging through either a Purge or Al Merayah.
RE: Have an option to opt out option
With that said I am not indefferent to your request, as they will occasionally activate at times of duress and intensity while we are in the heat of battle. I am not exactly certain what you refer to by an opt out option. If you mean an Admin Setting then I wholeheartedly support that. However, if you are requesting they be deactivated by default on Officials, then that is a polite ‘no’ from me.
A far more constructive approach would be to lobby Funcom to reassign the button to instigate the fatality in the first place. For example, I personally have previously suggested they reassign it to the Interact/Harvest button for consoles, PC players can have any button they desire and I will raise no objection.
Reassignment is a better way forward than disabling features.
PS- Funny how Funcom has a tendency to ignore the UI changes we all do clamour for and request, but then make push unpopular and unneeded UI changes no one wanted, and where things were already functioning well beforehand.