If we're talking about TCW/Rebels voice actors, Filoni talks to them a lot about the characters, so they would have insight into their own characters at least.
So when for instance the Kanan voice actor, and the Maul voice actor both confirm that Kanan is ordinarily no match for Maul, then we can take it for granted that's how the Rebel creative team see it.
But probably can't take movie actor statements as seriously, unless they say "George explained it to me like this..."