I spent twelve years living in (or as the locals say 'on') Bermuda.
A very remote place but not thought of as such since pretty well the nearest land is New York and so its not thought of as such. Extremely unpredictable weather - very sudden sharp squalls appearing from nowhere and in winter severe gales (shes making up a little in localese) are very very common.
In summer when the Bermuda Azores high pressure is in place the air is still and the sea a flat calm with no horizon as has been pointed out. Even more scary were days with lovely fluffy white clouds because they reflected in the sea and produced not just uncertainty over a horizon but a completely false picture .
Another good illusion if approaching from the east /North east (ie coming from London) if there some clouds around was that it was hard to tell the island with its odd shape from clouds when looking into the late afternoon sun
So no dragons or monsters but plenty of hazards for smaller ships and flying light aircraft to Bermuda would just be insane although it happened very very occasionally. So no mystery to the 'triangle ' from my experience but it didnt make it any less of a danger and the occasional feeling that you really were along way from anywhere alone in an ocean wilderness