I think what they are trying to say is all the building materials and measuring tapes are designed with halves quarters, eighths, etc. in mind. But obviously that could have been done in metric too. But 2 and 5 are the only common factors in metric. 12 inches in a foot means 2 3 and 5. 5280 feet in a mile is similarly dividable. One of the reasons metric time never took of was because we have more factors in 60 and 24 than in 10.

> It seems that the US, Myanmar and Liberia, the current users of the imperial system [...]

Nitpick: That's wrong. Neither the US, nor Myanmar use the imperial system.

The US uses US customary units, while Myanmar uses traditional Burmese units of measurement. Neither of which are imperial units (as defined by the British Weights and Measures Act) and only US customary units are related to the imperial unit system.

The cost isn’t that minimal when everyone has materials denominated in customary units anyway, tool sets in them, and so on, and the benefit isn’t that big when the industrial and scientific applications that really would most benefit are already done in metric.