People disobey in the face of incredible odds anyway.
But also, god could just not tell us what to do. The limit to our freedom isn't coming from our knowledge that he exists, rather, its coming from him telling us what to do.
But even further, I don't really understand. If there's a bunch of things I'm supposed to do in order to avoid hell, I don't know how to conclude that its a good thing that this information is being hidden from me. My eternal soul is at risk here, and I'm being kept in the dark.
If I knew a town was going to get invaded next month, and everyone in that town would get tortured for the rest of their lives, I would surely try everything I can do to convince people to leave the town.
I wouldn't leave little clues of the upcoming invasion in order to prevent from messing with their free will or whatever.
On top of all of this, knowledge does not restrict freedom, it empowers it.
I can't make good decisions unless I have the information I need.
Its up to me to decide if I want to continue sinning, knowing I might go to hell for it. But I can't make that decision if I don't know this is a thing I need to worry about.
My decision making is being robbed from me.
It would seem to me that the situation is exactly the opposite. If you keep me ignorant of some information that would effect my decision making, you're impeding on my free will.
If I know that telling you about the discount at KFC would make you more likely to go eat there, and so I intentionally don't tell you, I'm manipulating your decision making process, your free will.