Well, the team he did put together was a bit better, as the Arroyo (2B), Hernandez (CF), Verdugo (LF) Renfroe (RF) arrangement actually worked out pretty well. And Marwin was certainly a capable defensive player whose bat was probably supposed to get him more time at 1B.
But health has also played a part is the poor defense. And if any sort of major mistake was made by Bloom, it was his bizarre desire to collect multipositional players as if teams need more than one of them. Maybe sticking with some players who have actual repeated MLB experience at one position might help. Kike was enough to fill the versatility needs. Adding Marwin was just flat out redundant. Bringing Danny Santana and Taylor Motter into the mix is evidence that maybe Bloom has some sort of addiction problem going on here...