I have seen these ads telling the young people to become engineers and scientists for decades, there is the scare of a shortage. I cannot recall any ads in favor of accounting and business studies yet that is where many students end up.
It could be big business and government trying to get cheap labor, it could be altruism where the promoters really think that 'we need' more technical people.

If masses of young people decided to study science engineering and technology what would happen? Would clean water be available to all, would cancer be cured?
No, there will not even be more research and government spending on carbon change science, health administration, weapons, tide barriers and sea walls. The major effect would be more qualified people driving taxis.