If I would harbour a guess, it's just down to Singaporean's mentality.
Even amongst young ppl, there are many who do not want to risk investing in stocks, not even ETFs. Up until recently, banks offer all sorts of saver plans to earn higher interest, and many I know are satisfied with that even if they have to meet the cumbersome requirements and place their deposits with various banks just to maximise the interest rates. And then there was SSB. With i/r now lowered, maybe things will change eventually?
For those who venture into stocks, there is significant outflow into foreign markets, simply because of the negative sentiments towards the outlook of STI. If the GME saga has shown anything, it is that sentiments play a equally important role, if not more important, than fundamentals. So seems like yes, the negative sentiments will lead to a self fulfilling prophecy..