however you have to make decisions on your own, that’s why Hashem gave us bechira.
No, He gave us bechirah so that our actions deserve reward, and He instructed us “uvacharta bachaim”. Bechira doesn’t mean it’s a free-for-all.
There were gedolim who told their chassidim to stay in Poland and Germany during the war and boy were they wrong! Gedolim are human beings; they are not perfect.
But I guess you’re omnipotent? See, what you’ve just done is create a straw man to argue against. Gedolim don’t have to be perfect or be able to see the future to be the safest bet to follow.