I thought such system was in place long time ago? Back in my days you couldn't proceed to secondary if you fail BM too, so this is just increasing the threshold?

Anyway, I think more emphasis is needed on spoken BM than written BM. Many nons can score A+ for BM but when it comes to speaking they stammer or forget the words. Being able to write proper BM isn't of much importance when you work in the private sector, and when you actually need to write you can easily google.