Actually, for many years, the China Open 9ball offered a more elite field than the US Open 9ball, but the over the past 7 years or so, the US Open 9ball field has caught up with and, quite possibly, as you suggest, passed that of the China Open. Still, a China Open title is every bit on a par with the US Open 9ball as a resume item.
With the exception of the World 9ball, the China Open (and possibly the almost as difficult to win "All Japan" Championship) were the only events in which all the stars of Asia participated until about 2019., As tests, these events were very stiff and only the giants of the game managed to capture these titles. Shane has played in over 80% of the Cina Opens and All Japan Championships ever contested and has never won either. Shane, Josh, and Fedor have all failed to win the All-Japan to this point. These are two of the most rigorous tests in the history of our game.
Still, in the end, I'm conceding your point. Since the Matchroom takeover of the US Open 9ball in 2019, it has offered an almost unimprovable internationally comprehensive field, and I'm excited that I'm attending the 2025 edition next month.
Thanks for your well-judged thoughts here. The continuing evolution of the US Open 9ball, which may be on track to become as stiff a test as the World 9ball, is something every American pool fan can celebrate.