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Not the Strait of Malacca per se; but the adjoining Singapore Strait, which any vessel must also traverse whether on an East-West or North-South passage: absolutely. Here's a comparison to Gibraltar at roughly the same scale:
As can readily be seen, both straits are roughly the same width, a bit more than 10 km at their narrowest point, but the Singapore Strait has additional hazards in the form of much shallower water and numerous shoals. Navigating this while opposed by enemy vessels, without local pilots, would be hazardous in the extreme and likely require both favourable winds and tides.
Attempting to avoid the Strait by instead navigating through or around the archipelago due south of Singapore is not likely to have more success. The headlands would readily allow for lookouts and signals that would transmit news of any such attempt to the main base quickly - probably far more quickly than vessels of the time could navigate unfamiliar water. Those channels are also considerably narrower than the main strait, though two have deeper water.