I like both, but I've always leaned toward science fiction myself. I have an easier time finding deep and thought-provoking stories in the science fiction genre, and I tend to prefer its more emphasis on exploring what its possibilities mean and using them to examine ourselves.
I think sci fi asks more interesting questions, and opens up more assumptions about society being questioned as norms in how it develops its world building. fantasy can do that, but 9/10 is just Tolkien shit again BUT THIS TIME WITH X new CRAZY idea for their politics/magic system/bad guys, that actually are not all that new