Most typing was once done by men
The keyboard layout as we know it today was invented by Christopher Sholes in 1868. His first typewriters had the letters arranged in alphabetical order but he changed it to the QWERTY arrangement. In 1873, he contracted the Remington Arms Company to build and market the typewriter. It did not sell well for the first 15 years.
In those days, most typing was done by men as the representation of women in the workplace was very low. Today, women do most of the typing jobs – although an equal number of men use a keyboard because of personal computers, laptops and other suchlike electronic devices.
The QWERTY arrangement is by no means the most efficient. It also favors left-handed people. The DVORAK keyboard layout is more efficient. But QWERTY has remained the standard layout.