It's most likely a combination of things. The tire tread and tire itself are probably reasonable at this point. Tire inflation pressure is high, but in my experience with my S reductions made only a minor difference. I do think Tesla's simply carry more noise from the suspension through to the chassis/body of the car. My suspicion is that they simply didn't invest a ton of time tuning this with either strategic weight placement, dampers (shocks/struts) or bushing compliance. Once that vibration/noise is present, you are stuck "chasing" it and patching around it with thinks like mass dampers. Beyond that, you have a general lack of noise barriers/blockers and less sophisticated door and window sealing. It doesn't take much of an opening for noise to travel. As an example turn on the radio or TV in a room and then start to slowly shut the door into that room. Notice how the TV noise outside the room stays almost the same right up until the door is close to being completely shut.
Finally, a lack of noise absorbers (like Thinsulate) is likely present and hard surfaces like that big glass roof do a great job of bouncing sound around (think about the difference between an empty room and one with carpets and furniture in it).
In short, no "silver bullet" typically when it comes to noise and this is why noise is part of "NVH" - Noise, Vibration and Harshness. They are all components that tie together.
