Did you read up more on the circumstances that BOPE was formed
to deal with?
Policing is a thing that evolves with the community.
Rio's slums and favelas filled with armed criminals/narcos and
high crime rates are a huge contrast to the relatively crime free
HDB dwellings of Singapore.
STAR team is part of the Special Operations Command which
includes the Police Tactical Unit.
The PTU troopers ride along in the "ang chias" that you see.
They have evolved to more smaller and mobile units travelling in
the TTVs compared to the past when they travelled in buses.
They are the closest you can get to BOPE in terms of structure
and purpose. But you have to note that policing in singapore is
totally different from policing the favelas of Rio. The theatre of
operation is different, the threats are also different.
Which means the way they operate are also different.