Not at all.
This is basically true of all decisions, just as it's true of an empiricial reality that it exists prior to our being aware of it. The free will debate is not about
how decisions get made but about who makes them (you vs. external factors), so how is this fatal to free will?
That we are not conscious of decisions until after we have made them is natural to the empirically thinking person, and in no way a threat to free will.
To reword this in light of the abused terminology mentioned earlier: 'But you become aware that you made the decision.' But if not you, then who?
I refer you to
post #10.
I don't see the free will debate as being about whether the choice is consciously or unconsciously made, but whether you or some external factors are given the credit for the choice.
We made choices based on reasons, influences, opinion, versions of truth, and all sort of factors, but it's that
we made the choice and not those factors that is an indicator that free will was in play.