I was playing in a creative world to test the End and when I entered, my character just fell for a long time until the obsidian base spawned. Defeated the Ender Dragon. Threw a ball at the End Portal, it got A LOT OF TIME to teleport me. On the other side, I thougth I was unlucky because there was nothing nearby, but actually the world generation of The End was (is) just EXTREMELY SLOW now.