Steve got one-shot by Thanos in a 1v1 whose stated to be weaker than Hulk by the Russos, just a more skilled fighter.
Red Hulk certainly has strength and speed feats in the film, but besides that, BNW’s director said he scales to the Hulk.
Steve fought against Loki, Ultron and Thanos for a while prior to having mjolnir, Red Hulk himself has no feats so how would Sam barely injuring him scale him above Steve fighting any of those people in any capacity?