If you’re copy-pasting this, make sure your uid and gid matches of course.
But the key thing for Steam is you need to have your compatdata folder on a Linux partition, because Proton creates folders with invalid characters (like :). windows_names would prevent that of course, and thus prevents corruption, but it would cause Proton to fail since if can’t create those folders/files. So you’ll need to symlink that folder on your NTFS disk to point to a folder on a Linux partition.