One could not imagine Linux without X11 in 2003. And in 2003, the situation between Microsoft and Linux was rather tense.
That said, I managed to somehow forget about Xbox. I agree it makes sense that Sony couldn't launch an "X console" with a gigantic X on the side.
So yes, I want thinking it through. I do however think that using this trademark against X.xom would be ill conceived, no matter how much I hate Musk. If they start moving into gaming it might be different though, so fair enough.
Thanks for making me think it through more! :)