Well yeah, but they could use the brand, likeness and source code of the original; if they created a clone (and there are clones, hundreds of them) it would NEVER have gotten even one percent of the share. Plus there's the merchandise. There is an existing market for Minecraft merchandise, and a clone could never even get close to that network.
I mean how many kids do you see walking around in "Cube World" T-shirts? CastleMiner? FortressCraft? Take your pick: https://www.reddit.com/r/Minecraft/comments/lx5g3/complete_l...