Who said the Uzumaki were a support group? The Clan members with no identity or teachings from the Clan were powerful enough with their Uzumaki blood. That being Karin in example who wasn't taught anything, but was capable of using her own abilities and activating the Uzumaki Chains to damage SS.What no way Uzuamki is not that strong imo. A support group I would rank them C or B tier and thats being nice. Peak Senju and Uchiha stomp.
They were feared for their sealing abilities, and for that reason they became eradicated. Not to mention they are direct descendants of the Senju, whom are linked to Asura. To be totally honest, I would put the Uzumaki Clan right below the Senju/Uchiha in the Tier list, but I thought A Rank was better for classification since we don't know how well they could perform in combat.
However most Uzumaki Clan members we've seen are pretty powerful despite the lack of training from the Clan itself. Putting them anything below that is a disgrace to what the Manga has shown.
Especially since next generation Uzumaki stomp the Uchiha, hard.