Thailand’s goal of becoming Southeast Asia’s leading trading centre for digital assets has suffered a setback, following moves by regulators to tighten rules in the wake of trading irregularities and the collapse of a major acquisition involving a crypto exchange. The country was the first in the region to implement digital-asset legislation in 2018, which helped attract droves of so-called millennials to put their money into cryptocurrencies. The Securities and Exchange Commission (SEC) licensed six platforms as exchanges, including Bitkub Capital Group Holdings Co and Zipmex Thailand. Bitkub…