Critics from sites like The A.V. Club have praised the episode for its "visceral" and "painful" look at relationships. It is frequently cited as the episode where the show truly "grew up."
Reviewers often point to the "shape-shifting" scene as the episode's climax. Amethyst transforming into Rose Quartz to hurt Greg is one of the series' darkest moments, illustrating how her own self-loathing and resentment can manifest as emotional cruelty toward those she loves. [S1E43] Maximum Capacity
"Maximum Capacity" is an essential watch that trades the series' typical whimsy for a heartbreakingly human story. It doesn't offer a clean resolution, which makes it feel all the more authentic. Steven Universe S1E43 "Maximum Capacity" Recap - TV Tropes Critics from sites like The A
TV Tropes notes that this episode is crucial for understanding the depth of Greg and Amethyst’s friendship—and why it eventually had to fracture after Rose’s death. Amethyst transforming into Rose Quartz to hurt Greg
The episode highlights how Greg has tried to move forward with his life, while Amethyst is still stuck in the past. Her reliance on the "Li'l Butler" tapes is a metaphor for her inability to face a world without Rose.
It provides a rare look at "Adult" problems in a show seen through a child's eyes. Steven’s role as the "responsible" one while the adults regressed shows the impact of their unresolved trauma on him. Critical Reception