The fan survey seems even more un-explainable this season than before. For example, my "I am familiar with the star players, and am not afraid that they will be transferred" has been at 1 ball I think all season (didn't check it early on) and just gone up to 1.5 balls, yet I've sold only 1 player in 3 months and that was last season
My thought on this (as a user, no inside knowledge) is that we in general aren't treating that as two separate conditions and maybe that causes confusion. I think the "familiar with star players" part would be best approximated by sorting your players by salary and then looking at how long the highest salary players have been on your team, while the "am not afraid that they will be transferred" is the part about how many higher salary players you've sold recently. So not only does selling off higher-end players lower that value a bit, but if you fortify your roster with higher-end players, that may also lower this value somewhat as the fans are not familiar with those players initially.
Of course, I've done absolutely no research on any of that, so I wouldn't give what I say any more weight than any other anecdotal findings of any other user.