Hello friends 
I have heard it said that the Buddha didn’t speak Pali, but spoke something similar to it. If I’m completely honest, when hearing that it very much took away motivation for me to learn Pali.
Fast forward a couple of years and I now have a lot of motivation and really want to go deep into Buddhism and hopefully even call myself a Buddhist at some point before I die. I purchased a Pali course from the University of Oxford: https://www.ocbs-courses.org/ In this course, they actually claim that the Buddha spoke Pali. This course is given by what I believe to be top historical/secular scholars and of course part of Oxford University. This very much strengthened my faith and motivation to learn Pali.
I forget in which lecture I heard that the Buddha didn’t speak Pali, but spoke some dialect similar to it, but I’m very certain I heard it. Does anyone here have any input on this? Of course even if you want to argue that the Buddha didn’t speak Pali then I welcome your wisdom .
Or was I mistaken and there was never the scholarly consensus that the Buddha didn’t speak Pali?
The reason I believe it is important that the Buddha spoke Pali is because there would inevitably had been mistranslations and meanings lost in translations if the Buddha taught in another language and then that was translated into Pali. Just look at critical studies of various suttas where they compare the Pali and the Chinese versions. Sometimes the translations into Chinese will mistranslate what was the original in Pali. Also, if the Buddha didn’t speak Pali, then it makes little sense to look at the etymology of words in Pali, since maybe the word the Buddha would have used a word that had an etymology that was completely different compared to the Pali one.
I’m feeling so good these days, getting back into meditation, spending my free time with meaningful studying of the suttas. Oh, I better work as hard as I can at the moment because certainly anicca will set in and try to change the situation 
Have a good day.
PS: The video costs money so I can’t don’t think it would be ok if I uploaded it and shared it, but I’ll try to summarize what they said.
There are 3 main languages. Magadhi, Pali and Sanskrit (sorry I don’t use the marks above the characters, I need to figure out how to install that).
Magadhi is the dialect of the Mauryan empire.
The Buddha wanted to communicate his teachings in a vernacular language, not a scholarly one, in fact, he forbade translating the teachings into Sanskrit since he wanted them to be in the vernacular of people.
Pali was a lingua franca in north west India at the time of the Buddha.
The Buddha traveled a lot over his life, so while traveling he had to communicate in various dialects.
The Buddha was awakened in Gaya (which is in Magadha)
The Buddha was born in Kapilavattu (Which is well north west and most likely they spoke Pali there)
The Buddha spent a lot of time in Savatthi (This is even further west than Kapilavattu, there the Buddha would have certainly needed to speak Pali).
Given that the Buddha wanted to use a vernacular, not Sanskrit, and he lived a great deal of his life in north west India and the fact that he had to be able to communicate with people in order originate any teaching, it makes sense that he would have taught in Pali.
They conclude that the language of the Buddha was Pali.
. Anyway, it seems to not be 100% impossible that the Buddha spoke Pali, I certainly would like to believe so. So I will keep studying and see what I come up with. But it is important to not jump onto the conclusion that you would like to hear, I certainly don’t want to believe in some creation science version of Buddhism, where I substitute a belief in a young earth for a belief that the Buddha spoke Pali.