The changes were blogged about starting back in Feb. I solicited feedback for months. Please read the blog articles for the "Why".
http://blogs.vmware.com/vsphere/2015/02/vsphere-6-0-hardening-guide-overview-coming-changes.html
https://blogs.vmware.com/vsphere/2015/06/vsphere-6-hardening-guide-ga-now-available.html
mike