In the end the choice remains with Bayern because after all, even though in this match Galatasaray is playing at home and with a good match record in domestic competitions and the Champions Legaue but still they are still far below Bayern so I will not see any other possibility than 3 points for Bayern in this match.
It seems that these two teams have never competed in the UCL. If I'm not mistaken, then this is the first game of both teams. Of course logically and statistically the condition of the Bayern Munich team will win and indeed in the betting market many hold Munich. But with the current conditions, the match will be held in Galatasaray, so the chances of Galatasaray getting points are quite open. I was a little hesitant to choose Munich with a one-goal difference because a draw seemed possible. 
the h2h is not really applicable because it was half a century ago and not important to be used as a benchmark.
This is a new era but even though Galatasaray are consistent now and have the advantage of playing home I don't think the result will be too different because the possibility for Galatasaray is only a draw in this match but even then it is difficult because it is very rare for Bayern in the Champions League especially for the group phase they get a draw because they always sweep the victory in this group phase.
So I remain confident that 3 points will belong to Bayern.