I've been reading through the paper though and there's a lot there so maybe I just missed something.
I also agree with the observation that there is a correlation between dog size and intelligence. Intelligence is certainly a strong personality factor, and size is correlated with breed. I think this helps explain why so many miniature dogs are particularly "yappy".
https://data.world/sharon/what-is-the-correlation-between-do...
"But overall, only around 9 percent of dog behavior was explained by breed."
That's a lot if 9% of the time one breed is trying to lick you while the other is trying to bite you. I could believe that around 91% of the time you can't tell the difference between doberman and golden retriever behavior. It depends on the stimuli.