The whole Vision thing has always been weird to me. I got it, he got pierced through with a very special weapon. But then, instead of trying to split the Stone from Vision in Wakanda, couldn't they like... repair him ? They have infinite vibranium and insane technology, sure they could have done the same thing that was initially done by a normal pod a few years before.
All they had to do was to fully repair (and upgrade...) him and Infinity War was over