TL;DR from Julian Gough blog post[0]:
"I wrote the End Poem for Minecraft, the most popular video game of all time. I never signed a contract giving Mojang the rights to the End Poem, and so Microsoft (who bought Minecraft from Mojang) also don't own it. I do. Rather than sue the company or fight with my old friend, who founded the company and has since gone off in the deep end, I am dedicating the poem to the public domain. You'll find it at the bottom of this post, along with a Creative Commons Public Domain dedication.
Anyone can now play with it. Have fun."
[0] https://theeggandtherock.substack.com/p/i-wrote-a-story-for-... (this link was found on the Reddit post)