No, player -character separation is a myth, an attempting to force it is actively metagaming. Making decisions for the character in the fantasy environment is roleplaying, but it can't be done by ignoring player motivations unless you intentionally try to metagame to do it.
Certainly in-character motivations can be considered by a player against any other knowledge and given precedence if it conflicts, or find a compromise. For example, if your character is a mercenary who wants hard cash up front, you're likely to look for ways to get XP that also get hard cash up front first. But in the absence of that, or even when it's not a total conflict, player motivations
will influence decision making for the character.
It probably doesn't.