I'm sorry but this idea that a studio of 800 people at its peak failed because they made a second game for the first time in 15 years is just stupid beyond all rationale.
The actual reason the game failed is because top leadership deliberately mismanaged the studio to inflate its value so they could directly benefit from its acquisition. EVERY problem with D2 that led to this is downstream of that reality.
Dropping Destiny 2 for Marathon is certainly a choice.