[LD] Excessive autonomous 'Speak dead language'/Relationship deteriorating

This skill is wrecking relationships across my households that has sims with the skill. I understand you've decided this is not a problem and I'm not here to argue that. What I would like to know is how can I remove this skill from my sims so that they don't speak this dead language to other sims anymore? I have researched and anything I have found does not work. 

Like using stats.set_skill_level Minor_Thanatology 1 and then going to manage worlds, loading another household and the going back. After doing this the sim I am working with still has Thanatology 5. This had to end because it just caused her husband to have a hurt sentiment because he feels like she has wronged him. THAT is all this skill seems to do and I am tired of it ruining good sentiments that I have worked on them building.  I do not have mods and I am not interested in putting them back in my clean installation at this time. This sim has completed Ghost Historian but I don't see why that would prevent the cheat command from working. She is not employed so it's not needed for a job. Can you at least tell me how to get rid of this skill please?

I am going to have to agree with this. I am playing a family where the mom runs a funeral home, daughter is a reaper and dad is a ghost and is a patron of the arts. I had mother and daughter max thanatology because of a wall message I read that said something like her pronunciation wasn't what it could be. I think that even though it is maxxed out, they need to speak it to get better at pronunciation. This seems to have helped somewhat and they will get positive interactions MOST times when speaking it at each other. However, it still happens plenty enough that the interaction will fail I guess and the interaction will have a negative impact on the relationship. And it was more so between wife and husband to the point of festering grudges and hurt sentiments. It was so detrimental I had to put them in relationship counseling and dates to fix it. 

So when it is said "functioning by design", WHAT purpose is this supposed to serve? Usually something is designed to have a purpose. I mean I have to watch my sims closely at home to make sure this doesn't wreck their otherwise perfect relationships and I cannot take them out into public unless I absolutely have to. So if the by design is to make these sims anti-fun and non-socializable, then you're rocking it I guess.

Yes this design choice needs revisiting. It makes Sims with the thanatology skill spam it endlessly making them not have any other personality other than be possessed 24/7 which is ridiculous. I had to cheat the thanatology skill away and cancel autonomous interaction every time and it's honestly ANTI-FUN. Not to mention them giving people grudge sentiments that are PITA to get rid of.

Adding that even if both sims have an interest and skill in thanatology, the relationship will too deteriorate.