Thank you for sharing this! It's the same w/t my undergraduate professors (liberal arts college; so no graduate-level experience). Almost all of them think getting a MA is unnecessary and a waste of money basically. It seems this is the general consensus of this forum as well: only get an MA if 1) it's fully-funded and 2) if you have a particularly weak component in the profile that a MA could help.
But now I realize the competition has become so intense (especially for top programs) that a MA will give an inherent advantage over BA-only applicants (regardless of the actual profile?). Or it's very possible it's only an issue for the field of China I guess. One possible reason is the China filed has additional supply of applicants that many other fields don't have. A lot of international students from China wants to study Chinese history in the U.S. and typically if their undergraduate is in China, they have to do a U.S./UK/overseas MA to be competitive for PhD programs. For other fields like US history and European history, most applicants are domestic students.