You can't argue free will
Hear me out: my premise is that many new posts here are using the ordinary "folk concept of free will", rather than an explicit rigorous philosophical definition. I see some arguments for/against determinists, all seem to be inadvertently using, or sneaking in, this folk concept of free will, which makes arguments pointless.
The folk concept of free will is part cluster concept and part psychological construct. (This is different from philosophical definitions.)
A cluster concept is a collection of traits. For example, a "fish" is something that lives in water, has a jaw and bones and scales, and lay eggs. But mudskippers can live on land, hagfish have mouths but no jaws, sharks have cartilage skeletons, etc. So free will operates the same way. Exceptions do not destroy the concept; in fact, this flexibility is a feature of cluster concepts.
A psychological part lies in how free will is a core part of a web of belief. It is tied to a person's identity, morality, sense of purpose, happiness, what it means to be human, and many more. To attack or defend free will, is to also attack or defend a person's entire worldview. A lot of free will debates instead become proxy wars about morality, humanity, etc. Free will can't be debated in isolation until you untangle that web of beliefs, and that is unique for every person.
This folk concept of free will is completely fine for casual conversation or approximating human behavior, but can't precisely describe reality. This is where philosophical definitions comes in. They are logically rigorous and precise. But as such, they are at best, a tiny subset of the folk concept of free will, and at worst, incomprehensible or incongruous to the public.
Ultimately, if two people debate free will and either one is unknowingly using the folk concept, the debate will devolve into arguing for argument's sake.
(FYI. This post has been inspired by "Why Humans May Actually Be Fish" in which Hank Green ends the video saying that taxonomic "fish" is no longer used in scientific conversations, but "fish" is still useful in other contexts. So I feel that arguing against existence of "free will" feels like arguing against the existence of "fish".)