The mandate part seems insane to me, an American. If the country wants 42 holidays that's fine - just don't attempt to stop me from getting ahead.
Besides, it's the mandatory part that I find problematic. If I want to open my doors for business no one should stop me for a holiday of all things.
Lower limits - I'm not sure. This is no longer the early days of the industrial revolution so we're not throwing people (children in particular) down chimneys to clean them and working conditions are much better, but at the same time they are children with brains that aren't fully formed so their judgement isn't exactly reliable. If they're working in a family business or similar that seems fine to me.