Cooper was being recruited because up until a week or so ago, Tennessee still lacked an elite center and she is the second best in the class. As I said, Russell's commitment addresses that need.
I don't know of anyone claiming Tennessee is now going to win multiple titles, but it wouldn't be the first time a Tenn or Uconn fan has made a bold and brash proclamation after landing a good recruit.
As far as USA ball goes, Russell shot 64% this summer and was 7th on the team in shots attempted. She made 1 shot less than Greenwell and 11 less than Deshields yet took 35 and 58 less shots, respectively. She led the team in blocks and was second in rebounds-a stat line that speaks of an elite center on a team of elite players IMO.
On pretty much the same team, sans Deshields, the summer before she was second on the team in scoring and set tournament records with her 11.4 rebounds per game and 4 blocks per game.
If you want to judge her based on these 13 total games, I would think Russell has more than established herself as an elite center prospect.