That essentially means that it was. If it wasn't they would have denied it and released data.
> but its manual does warn that the system is ill-equipped to handle this exact sort of situation: “Traffic-Aware Cruise Control cannot detect all objects and may not brake/decelerate for stationary vehicles, especially in situations when you are driving over 50 mph (80 km/h) and a vehicle you are following moves out of your driving path and a stationary vehicle or object is in front of you instead.
Just for those unaware of Teslas previous handling of other crashes, this is them waving a huge flag saying "We fucked up and we know it".
I wonder how that call went "Hi Tesla, my self-driving car just drove head-on into a stationary firetruck" "Ohh... did you read the manual? It's supposed to do that, so it's basically your fault!"