Depends on the kind of sleeper you are. Personally I can't sleep even in the summer without some amount of weight from fabric on me, which I know doesn't make much sense but it is what it is.
My roommate tosses alot when sleeping and a really heavy blanket keeps her still, which she says helps her get a deeper sleep
I have a 7kg weighted blanket that sits on top of my regular blanket at night and I love it. I feel like don't wake as easily, and overall sleep better. And it's so comfy.