When Should Elementary School Kids Start Learning to Code?

My child is 8, and these days they've been watching block-coding videos on YouTube and following along. They seem interested, so I'm trying to decide what to do for them.

People around me say to start them on Entry or Scratch, but I'm worried it's too early and could actually make them lose interest. I'm also not sure whether I should send them to a coding academy or just let them learn through play at home.

I'd appreciate advice from anyone with experience.