The changes are listed in the release notes for what is new. That said the risk assessment, file classification and expansion of features required a review of the minimum requirements which have not changed for a very many releases. Smart Classification usage requires further resources.
Having seen issues with sizing when Administrators added many infrastructure devices to the environment monitored without expanding the resources available, the decision was made to better size the requirements to the application.
When clients reach out to their sales representatives and plan new implementations or expand current environment to the current capabilities of the latest release there is a new sizing guide which can be used to gauge the environment to the intended usage of the application.
I hope that scopes out the reasoning for you.
Rod
