Would you like me to connect you with one of our compliance officers so that they can give you the whole background to why Singlife doesn't accept US tax residents into our product?
No, you can post your compliance officer's purported rationale here. It won't actually have any legal or regulatory merit given that Singapore and the United States long ago concluded their FATCA Intergovernmental Agreement (IGA) (linked previously), and everything in the IGA is bog standard KYC stuff you already collect. Your compliance and reporting requirements with respect to U.S. persons residing in Singapore are exactly the same as they are for any/every other customer you sign up residing in Singapore. That's the whole point of the now half decade old IGA.
Unless your product is registered with the U.S. Securities and Exchange Commission (SEC) you are not (per U.S. law) legally allowed to
solicit business from U.S. persons -- no ads in any U.S. edition of the Wall Street Journal, for example -- but if a U.S. person knocks on your door, that's perfectly legal. Other countries have similar laws or regulations.
I would add that your competitors, at least most of them, seem to understand the facts I've outlined above.
Fix this, please. It's embarrassing.