I thought it might be interesting to philosophically-minded readers of VP to see her defense of her belief that free will doesn't exist.
Much of what she says in the video is inarguable, but her whole case is based on a single a priori metaphysical assumption. If that assumption is false, as I believe it is, then her argument collapses.
Her basic assumption is that naturalistic materialism (or physicalism) is true. She never explicitly states this in the video, or argues for it, but it undergirds pretty much everything she says.
Naturalistic materialism is the view that nature is all there is and that everything within nature is reducible to material stuff. Physicalism is the belief that everything we observe in the universe - and in the present instance, in the brain - can be explained in terms of physical laws and processes.
None of these - naturalism, materialism or physicalism - are scientific. Their truth cannot be demonstrated by scientific inquiry. They're often embraced by scientists like Hossenfelder, but they're both fundamentally metaphysical or philosophical hypotheses.
However, if they're false and if human beings do have an immaterial mind or soul which is not subject to physical laws, then no materialist or physicalist argument, like Hossenfelder makes, proves anything. Her argument is cogent only if one is inclined to accept her metaphysical assumptions.
Anyway, here's the video in which she presents her argument: