I don't think free will can be dismissed just because the framework that it runs on is deterministic.

Let's say you program a text editor. A computer runs the program, but the computer has no influence on what text the user is going to write.

I think that consciousness is a user like that. It runs on deterministic hardware but it's not necessarily deterministic due to that. It might be for other reasons, but the laws of physics isn't it, because physics doesn't prohibit free will from existing.

Consciousness is wildly complex. It's a self illusion and we really have no good idea about where decisions even come from.

If it is deterministic, it would have to involve every single atom in the universe that in one way or another have influenced the person. Wings of a butterfly and light from distant stars etc. Attempting to predict it would require a simulation of everything. That leads to other questions. If a simulation is a 1:1 replica of the real thing, which one is then real and what happens if we run it backwards, can we see what caused the big bang, etc.

So, even if this is about free will, the enquiry falls short on trying to figure out what even causes anything to happen at all.

If we are happy with accepting that the universe was caused by something before or outside the universe, then it's really easy to point in that direction and say that free will also comes from there - somewhere outside the deterministic physics.

Of course the actual universe and the laws of physics are really not separate as data and functions. The data itself contains the instructions. Any system that can contain itself that way is incomplete as proved by Kurt Gödel's incompleteness theorem. Truths do exist that can't be proven so perhaps the concept of free will is an example of such a thing, or maybe it's not. The point is that we can't rule it out, just because it exists in a deterministic system.

Personally I don't think it matters all that much. Similarly to how we can only ever experience things that exists inside of the universe,or see the light that hits our eye, we can also only ever hope to experience free will on the level of our own consciousness, even if we acknowledge that it is influenced by all kinds of other things from all levels from atoms to the big bang.