My personal view, you don’t have to agree,
I find the factory or workshop shirt making in Southeast Asia not that good, slightly better in Bangkok. Maybe those Italian luxury brands like Zegna, Canali, did not outsource to Southeast Asia factories, so they didn’t learn from the best. The Chinese factories got orders from Italian, French and US luxury brands for a long time and the shirt making standards are much higher.
if you have the time to visit a proper tailor in major Chinese cities, take a look at the workmanship of the shirts.
I am still thinking whether should I reveal the details of the workshops in my next guide on Chinese tailoring.
some local tailors have supply chain from China, e.g made suits, Qmenswear, red dot bespoke, you can see some suits and shirts with Chinese characteristics