Countering Sexism is Good for Business
As mentioned above the main reason that so many IT workers have to work long hours is cr*ppy management.
But how to get decent management in place? Getting rid of all forms of discrimination is a good first step. Having decent IT management is very good for the bottom lines of companies where IT is a big part of what they do (like Microsoft, Apple and the other tech companies mentioned as funding this initiative.)
As a woman who has worked in IT I have found that the most sexist men are usually a) incompetent, b) unsuitable for management and c) the beneficiaries of a vast amount of positive discrimination themselves - except they don't realise it, they just believe they have a natural entitlement to be given special help at school, training and a well paid job they can't really do.
Presumably if there were a few nail-bar chains who thought their productivity and profitability was threatened by unpleasant anti-male attitudes amongst incompetent and lazy female nail workers they would start a 'National Council for Men in Nail Bars' to do something about the issue. But instead these nail companies seem to have concluded there is no such problem.