The latest WordPress update breaks the FTP server capabilities. )
So don't update to 6.1 yet, because it will break the update possibility of your installation.
And you cannot update anymore after it.
I've created an issue for it (Technically the exists method of the ftpext filesystem always returns true for the default FreeBSD ftpd server)
The coming 6.1.1 version should have reverted this change, but when you already upgraded it's already too late of course ;-)
When you've already installed, to only way forward is to
copy the WordPress 6.0
wp-admin/includeas/class-wp-filesystem-ftpext.php file into the installation.
You can download this 6.0 file here (remove the .txt extension)