Hi,
Please don't be confused, because a clear statement has been made in the description of this setting, this is the description quote:
Show Microsoft Flow on forms and in the site map. You cannot disable Microsoft Flow once it is enabled in your organization.
Once Microsoft Flow is enabled in your organization, you cannot disable it.
If this helped you, I'd appreciate it if you'd mark this as a Verified Answer, which may in turn help others as well.
Best Regards,
Frank Gong