If you create a custom end dimension, with modified world height values, the obsidian pillars in the main end island generate all the way to the bottom of the world (See attached screenshots and json file, don't mind the overworld's height, I made it shorter so it took less time to generate).
Environment
Operating System: Windows 10
Java version: 1.8.0_51 64bit
GPU: Nvidia GeForce GTX 960m 2GB
CPU: Intel i7 6700hq
RAM: 16GB (2GB allocated to minecraft)
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We're tracking this issue in MC-86654, so this ticket is being resolved and linked as a duplicate.
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