Boot Camp assistant "Needs more drive space" even though i have enough

Trying to get dual boot for my mac and I ran into this issue.

And when I look at my drive status, this is what I see.

So maybe im doing something wrong but it doesn't seem right that I need "at least 39GB" when I have 46GB available

I do plan on upgrading the storage of this mac soon anyways if I cant get this figured out

The 46.1 GB may include what Apple calls "purgeable" space. This space can be made available but is not readily so. My suggestion is to clear off more space if possible and try again. I think purgeable space is space occupied by files and folders that haven't been accessed in some time.