No, that's not what you said. You said "your options aren't great without back tracking." Cathay is generally regarded as an industry leading airline (like SQ or TG) and flies the route nonstop, without any "back tracking." Not as frequently as the Star carriers that hub at those cities, which is not unexpected.
I'll concede that the others have more frequency - which is to be expected between their hubs (TG at BKK and SQ at SIN).
How's Star Alliance's options between HKG and NRT, the hubs of CX and JAL? Limited, as one would expect. CX and JAL fly it several times a day.
No different than Dallas-Miami. Star can't take you there nonstop. How's Star's coverage between New York and London? Not so good.
Each alliance has its strengths and weaknesses. As eolesen said, if frequency between Sex Tourism HQs Bangkok and Singapore is a priority, then OW is lacking. But there are numerous business-centric routes where Star is simply absent. Just like the routes where OW lacks coverage.
