When the govt (any govt) meddles in something, the situation always gets worse.
Meddling jack-in-office Despot LKY crushed the Chinese dialects, and in doing so inadvertently destroyed the younger Sinkies' proficiency in Mandarin. LKY thought that proficiency in Mandarin and dialects were mutually exclusive, a binary choice. Of course, like many other things that happened on this snot-sized tropical island paradise, he fucked up.
During gatherings with Chinese language teachers (the ones who taught me and the friends who chose to work as one), they have divulged how MOE had dumbed down the curriculum over the years, and added superfluous crap which hindered the learning process.
Maybe this was part of the plan: deliberately make the kids learn little in schools, so they go to tuition centres for extra lessons. I believe MOE 'profits' from registration and licensing fees.