Ask your friend what's the specific reason for that because if it's just about accessing through sportsbooks, there's no problem with that. He/she can access most sportsbooks while residing in an Asian country.
Exactly this thought came to me as well as just if somebody has to bet or gamble they can do it any of them irrespective which ever origin it could just one important thing is that should be a reputed and trustworthy where you do not end up getting scammed . Unless someone wants to takeover or buy some stake in a casinos etc then it could be different story to know about specific in Asian country.