https://minecraft.makecode.com seems like a simple way to teach a younger audience, but the architectural and licensing requirements are daunting, and for me, insurmountable. But, at that site, kids can easily generate the javascript... which would be great to plug into ScriptCraft, if compatible with ScriptCraft.

I've tried, but the underlying classes/functions are missing. For example, the first tutorial generates:

player.onChat("Chicken", function () {
for (let i = 0; i < 100; i++) {
mobs.spawn(mobs.animal(AnimalMob.Chicken), positions.create(0, 10, 0))
}
})

... but ScriptCraft knows nothing about the "mobs" class.

Would there be any (easy) way to get compatibility?

You can use Scriptcraft with https://play.magikcraft.io. It is a hosted solution with the entire Scriptcraft API available.

The editor supports TypeScript and transpiles the code when it streams it to the Minecraft server, although we don't have complete typings for Bukkit or ScriptCraft yet, so autocomplete / intellisense is not 100%.

There is an introductory guide here: https://magikcraft.github.io/magik-users-guide/

By "kid", I mean a 7YO... so they need something simpler, like the makecode.com reference above. Code.org has something similar, but it's not real minecraft (and it's mostly structured, and the kid already finished it all).