I’m interested in the answer. Did you confirm this with the tax office?
Even if it’s true, it’s probably pointless for non-Americans. As I understand it, the W-8BEN form on IBKR and other brokers basically removes all American taxes except the withholding tax for dividends. So they are not exactly taxed outside Taiwan.
Not to mention the wording that you need to compare the regular income tax and AMT calculation, and pay the higher amount.