He should get a foreign PR, reside in that country for a while and judge for himself.
Singapore has selfish people in the ruling party and the country has been divided into 3 classes of people; the 'supreme' who rules and make decisions without giving much thoughts to the citizens, the 'elites' who benefit much from the existing political system and they are well-protected and looked after by the 'supremes', then you have the commoners who are easily replaceable and form the majority. Read George Orwell's "Animal Farm" to get a better insight.
The 'supremes' need servants; just like Singaporean need maids; it doesn't matter whether they are 'filipinos', 'indonersians' or even 'singaporeans;, as long as it's cheap and can do the job, hence the influx of 'foreign talents', but that will anger the commoners who are the majority and may result in the loss of votes for the rulling party. The soultion is quite simple, 'dilute' the majority by giving citizenship to foreigners who will be grateful and support the rulers in election. Those singaporean who are not happy can leave; the 'supremes' and the 'elites' don't need you to mainatin their luxurious lifestyles, they can get cheaper people from overseas to do the job.
So, if your brother is a 'patriotic' Singaporean, he should stay if he has the means and courage to change the existing injustice in this country, if not, he should stay out of this country and wait for the right time to come home.