Also, free will implies there’s someone making a decision. What is that “someone” and where is it?

Yup, I agree it isn't something epistemically real.

The reason I still find the concept of free will a desirable fiction is that it pushes people towards doing things that benefit other people, not just themselves, without necessarily curbing down their power. You can use it for example to drill people "yes, you have the choice to cause harm, but you should not act on it".

...or something like this. It's one of those things that is rather clear for me in my thoughts, but not so much when worded.