Why does choice matter when determining the morality of an action?

I think there are a few different concepts being alluded to in this thread, so I will separate them here and give my 2c

Right and wrong - I think for the purpose of this thread, it’s worth being clear that we can talk about events in themselves being bad or good. We don’t need to begin from looking at why a person did a thing, and whether they acted freely.
So I would say, for example, that a person starving to death is a bad thing…yes we can add extra context on top to change the net effect (done as a protest, sacrifice, whatever), but that doesn’t change that, in itself, it’s bad. And so an action that caused that state, in itself, I’d be inclined to think was wrong unless and until someone can provide some justification. That’s the right way around to view things I think.

And of course it’s subjective why dying horribly is bad, but at least at this level there would be near unanimous agreement because humans are just wired like that.

Punishment - Having prisons, fines etc does not necessarily entail “punishment”. A justice system can be based entirely on deterrence, rehabilitation, public protection and recompense. And arguably this is the way to go; finding a kind of neurological lesion that causes someone to become a serial killer should not mean we must release all applicable serial killers…the reasons for keeping them locked up have not changed (although if we could correct that lesion, then the picture changes…)

Free will - As stated many times previously: I think this concept is meaningless. This is not the same thing as saying “There is no free will; we are just automatons”. I mean “free will” is the same as saying “p and not p” IMO; it’s meaningless and has nothing useful to say about choice.
I’m happy to elaborate, but I don’t want to hijack this thread with my pet tangent.