I bought it new. It was used by me in a prior filesystem (ext4) to attempt backing up files, so the drive had actively written user sectors on it before trying

I bought it new. It was used by me in a prior filesystem (ext4) to attempt backing up files, so the drive had actively written user sectors on it before trying out a linear log filesystem for the same backups. If instead I had used such a FS on the drive in its new state, there might have been a possibility of better performance, depending on the internal drive management software. The notion of returning it to a state where it considered sectors unused is also dependent on that software.