In primary children 'learn' a foreign language, but the truth is that they learn very little of use until secondary - at which point they may start from scratch with a totally different language. And many children never master any useful amount of a second language.
A wasted opportunity.
Why not teach children a second language that they can start using immediately, and that enables them to communicate with their peers? Particularly as this will include children with communication impairments in the peer-groups.
https://www.bbc.co.uk/news/education-51774535