It's the typical open source model. They are probably hoping someone else comes in to add the gameplay via modding.

they have, there are full minecraft clones you can download for it that work well

A full clone is not a very interesting game.

It seems like Minetest has more or less evolved from trying to be a Minecraft clone to trying to be Roblox, that's ... weird

Minetest has tons of games downloadable from a single click ingame.

So yes literally, hoping that someone else adds the gameplay via modding lol