I concur -- Its seems they went the Fisher Price direction for the new System Manager & didn't consult any real world sysadmins. Snapshot size? nope - gone. Nonsensical aggregate size -- yes. Its seems the marketing & UX team went crazy with the new design but really took away its usefulness to true sysadmins -- back to the 90's and the CLI...my word.
BTW - I'm running Ontap 9.8 P1...no change from RC1.