I think their owner's personality contributes partially to forming their personality because your personality is injected into your training and raising methods, but that doesn't mean they adopt their owner's personality.
My dog is my complete opposite. I'm an extreme introvert and he's an extreme extrovert. I'm easily stressed out and frustrated and he can handle anything and everything. I'm distrustful of everyone and he'd jump into a car with a stranger if they asked him to. I think the only thing we have in common is we both like food a lot.
Even the very fearful nervy senior husky I'm taking care of for my SIL has become much, much friendlier and outgoing in my care. I always expected my animals to turn into these unfriendly one-person animals but they always turn into outgoing, friendly, well-adjusted extroverts. What I liked most about my SIL's husky was that she was exactly like me, but now she's become so friendly and, well, 'normal', that I feel like our special bond that we had because we were the same and understood each other is lost because she's changed.