I read the sentiments (published in the ST) below. While I agree that the PSLE is an objective exam and was effective in sorting students for many years, I feel that it is no longer a leveller in Singapore.
When I sat the PSLE, whatever I knew, I learnt from school. Some of my peers did have private tutors, but they were not the norm. Expensive enrichment centres were unheard of. The students were more or less on equal footing then.
These days, affluent parents send their children to enrichment centres, some of which provide notes that are more informative than what schools give. Exam questions are harder than before and those with extra hours of exposure outside of school hours have advantage over those who do not. How many students without tuition / enrichment / home support thrive in the PSLE? I personally only know a handful. Unfortunately, statistics on the SES of students from each secondary school is not made known, so my views are merely anecdotal.
Schools also do their own streaming. Students who do well academically could be kept in the same high progress classes from Primary 3. It may be difficult for them to form friendships with students from other classes who may not perform as well as they do. Class divide may start as early as in primary school.
In my opinion, DSA also benefits the wealthy. Rich parents send their children for various enrichment lessons from young. Among my peers, most of our children either play at least one musical instrument or are involved in a sport intensively. However, I have also met children whose family are of lower SES. These children struggle with their daily dosage of homework and are not sent for 'talent development' classes. It is not impossible, but it will be harder for them to rise above their more affluent peers.