I'm confused about the word "Motherf*****r"

I recently learnt about the supposed origin of the word from slavery. Since then, I've been doing on and off research about the topic to see if it is true, however, I keep finding articles with very conflicting opinions and views that in my view kinda seems biased in a way. I am finding trouble finding reliable sources for either side too. So I'm just wondering. Is it something from slavery? Is it not? Is it in a weird grey area where we don't completely know? I'm just confused overall, and if anyone answers, please cite sources. Thanks

https://redd.it/1wqw4yf
@r_etymology