Just read this older Keef interview:
https://www.independent.co.uk/news/people/profiles/keith-richards-being-keef-306495.html
"And Brian? Is it all just too long ago now?
"Brian could be the most frustratingly obnoxious, nasty person. Which he never was until the minute we had a hit record. It was a fame thing, maybe; something seemed to snap in him. It could be that he thought he was numero uno and Mick didn't like that. I wasn't thinking about hierarchy at the time - I was just trying to find [the chord of] E7.
"We were pretty mean to him. We started to pick on him just to let him know: either you're in or you're out. And then he got more and more stoned, and he'd check into a clinic in Chicago while we were touring the Mid-West. I'm standing on stage trying to cover two guitar parts - it doesn't endear you to the guy.
"Later, I made a real effort to hang with Brian. This would be '66-'67, when we finally got off the road for a year. Everybody's getting stoned out of their brains and there's acid flying about. We were having a good time, but unfortunately there was Anita [Pallenberg - Jones's girlfriend before Richards "rescued" her from him], and then we get into that. That was the final nail in the coffin."
And this one:
https://www.rollingstone.com/music/...es-mick-jagger-and-the-new-memoir-life-52581/
"
You and Mick started the Stones with Brian Jones, and in Life
you are frank about Brian’s self-destructive flaws. You talk about his importance in the early days, but by the time of his death, any sentiment you had for him is gone.
I enjoyed his company, and I tried incredibly hard, in 1966, to pull him back into the group. He was flying off. But my attempts to bring Brian back into focus were a total failure. After that … [
long pause] He did some despicable things. The man was failing. He had been a strong man, but he was wiping himself out. Brian
demanded, you have to understand. And in a band like this, you also have to be supportive and giving. Having to deal with his jealousy, with Mick and me writing the songs, when you’re working 300-odd days a year — it becomes intolerable, and you can get really nasty about it. I tried to be fair to him. But to be honest, he was a bit of a bastard. And it doesn’t surprise me that he came to a sticky end."