Yeah uh...consider the work that goes into casting metal. Consider the importance of eliminating air bubbles impurities and other irregularities, especially if it's something that's going to take a lot of stress. Consider how fiddly this is with basically any casting, investment, even 3D printing can be finicky unless things are config'd right. Even the article brings it up:
So far, automakers have shied away from casting ever-bigger structures because of the "gigacast dilemma": creating molds to make parts of 1.5 metres squared or more boosts efficiency but is expensive and comes with myriad risks.
In case the story of the sub implosion hasn't already illustrated what tends to happen when some big-shot corporate fuckwit says they can handle, take all the above considerations and filter them through Tesla's level of trustworthiness. Add a dash of scummy practices like handing control of self-driving cars back to the user when it detects a collision is imminent so they can escape liability, in case you needed your memory to be freshened up a bit there.
Now consider that their intent is to use this known-to-be-risky casting method with the parts that hold up the battery and engine, and also the part that's going to be quite important in a collision, something that rather obviously puts metal through a very sudden and intimate stress-test...
