There are plenty of videos of stuck vehicles that have a hard time due to traction control disallowing power even with full accelerator pedal, this is not a foreign concept in a modern vehicle. Here is one example, they refer to traction control as the soup nazi, no power for you! : https://www.youtube.com/watch?v=WLVae7-N_Vs

It's a feature to look for in a off road vehicle if it has a traction control disable and even ABS disable on motorcycles, this is an explicit command to disable a safety feature that typically resets when power cycled. Not sure why FSD would allow overriding an obviously unsafe situation, the operator can disable the whole thing at any time if they wish to do so and go manual with a specific on screen command rather than hitting a pedal right next to the other stop pedal with your foot resting between them otherwise.