Free the Endermen

The advancement gained when the Ender Dragon is killed is called Free the End. What this implies is that the Ender Dragon enslaved the Endermen. Once the Dragon is killed, portals to the End Islands (and by extension the End Cities) appear. This is the only part of the game that is locked behind a boss (It is possible to skip the fight but it is a very niche strategy). It drops the Dragon Egg when it dies, but there is currently no use for the item. My idea is to use the egg to reverse whatever the dragon did to enslave the Endermen. I don't have any idea what the process would look like, I guess wherever Mojang would decide to take this from a creative perspective, but I have a good idea for possible effects: Endermen no longer get angry when you look them in the eyes or hit them, but they will still teleport; Shulkers become neutral mobs that stay closed until you attack them, after which they revert to the original behavior. Perhaps there can even be Endermen in the End Cities that behave like Piglins, but because of the dragon's influence their society is kind of barbaric--even more so than the Piglins. So they fight each other on sight. Instead of bartering with them, you can gift them blocks which they will then build a structure with, and finally a unique reward. There can be randomized scores for every block type per Enderman, and depending on the cumulative score of the blocks used to build the structure a better reward. Feel free to add on to this below.