Doubt that .
Some places offer more expansion room in terms of career
opportunities that Singapore does not have. Singapore does have
room for expansion in finance, banking , logistic management and
tourism areas.
However if one wants to do nuclear physics or even let's say marine
biology - they have to venture overseas. Even for certain sciences,
Singapore has not established itself as an internationally known
research entity yet.
And not to mention , there is almost no such thing as second
chances in Singapore. Overseas, I have seen nurses become doctors
/lawyers/statisticians etc but not in Singapore. Once a nurse,
almost always a nurse unless you want to open a medical related
business . I don't see people taking on another line .
Singapore in a way has her own advantages and disadvantages . So
you cannot say whether a singaporean would have made it bigger if
they had stayed in Singapore or overseas even. Why do you think the
government likes to send scholars overseas if Singapore was so
good? Heck even LKY's own grandsons did the IB instead of taking
the normal route of education that Singaporeans have.