Whether we have free will or not is independent of whether we want
free will or not. Some are prone to falling victim to an appeal to consequence here, and mixing up that because we really want free will it must be true. Whether something has bad or good consequences has no bearing on whether that something is true or not.
Even if there is no free will, we can't exist without assuming there is. A society which holds nobody to account for anything will quickly descend into chaos and in time become extinct. Therefore, we have to at least assume humans are agents which can be held to accountability.
Does no free will mean this though? Not having free will doesn't mean people can't be punished for their actions, or made to change their actions. If you look at people more like dogs (who for some reason aren't deemed to have free will), you can still alter the behaviour of dogs without saying they have free will
In the same way, you can still have deterrents, positive and negative reinforcements, these become things that are necessary for a better outcome rather than things to punish individuals. Perhaps
I mostly agree, though I don't particularly like the word "libertarian," and I'm not exactly sure what you mean by "libertarian free will."
Libertarian free will is one of the main positions one can take w.r.t free will, and it tends to be the default
human position. More or less:
1) Compatibilism: Belief in free will and determinism. That is, determinism holds but humans still have enough agency for responsibility.
2) Incompatibilism: Belief that free will and determinism are not compatible. This falls into three sub groups:
a) Hard Determinists: Belief that because determinism is true, free will cannot be
b) Libertarians: Belief that there is free will because determinism is false.
c) Hard Incompatibilists: If determinism is true there is no free will, if determinism is false, there still isn't free will.
Arguing against determinism isn't the easiest thing, though you can make some arguments using quantum indeterminacies. Essentially what a libertarian is suggesting is that our minds are free from determinism (cause and effect), i.e. we are little mini gods. You can use quantum indeterminacies to argue against compatibilism, but this still (if you say there might be true randomness) doesn't mean that randomness is under the control of the individual (which is what would be required for free will, the hard incompatibilist argument, I think). That is, even if you have true randomness which breaks determinism, that randomness must be under the control of the individual for it to matter.
Compatibilism isn't the free will people assume to be free will (that is libertarian free will). It isn't so much completely free will as "enough will for accountability" or something like that
The idea with determinism is it "holds enough" outside the quantum world to consider it more or less infallible. It is all pretty heavy stuff though (and I might well have messed some of this up, because my brain is poo atm