For those not based in the UK, I think the OP makes a very fair point. One of the main attractions of BA / OW for us (based in DXB) is the opportunity to choose from a range of premium airlines within oneworld:

• BA for all points west (although a lot less premium over the last year)
• CX for all points east incl. Australasia
• QR as an alternative to either (and until last week my preferred carrier to LHR)

Hence, with QR currently out of play due to the diplomatic incident, and if CX were courted by LH to jump ship to *A (building on current *A cooperation), that would indeed be a disappointment which could weigh in favour of EK / *A in the region (although not necessarily for me, for now). The only issue would be how SQ and OZ would view CX in *A.

Potentially, this sentiment could be repeated across other eastern markets, if BA / OW don't work to keep quality airlines within the alliance.