The point is you never know what police is looking for. What looks like a simple traffic stop to you can be police looking for a suspect, and by being cooperative, you risk incriminating yourself. It's not worth it, never.

Even if the intention is a simple traffic stop, police is incentivized to bring their numbers up, so anything you say during a traffic stop can and routinely will be used to pin higher offenses on you. Again, it's not worth it.