He probably didn't say it "on the record", but I have no doubt he said it. Probably yelled it from the crapper seat.
There’s enough “on the record” racism by LBJ that we know he was a virulent racist whether or not he said that remark.
Have to agree with you...he probably said that and variants of it many times.
Thanks for the image. I can just picture him sitting on the throne yelling that to himself.