PC Structural Integrity on Large Pre-made Buildings

[xXSandmanXx]

So I thought it would be fun to watch the giant smokestack structure collapse at the large factory. This structure is easily about 75 blocks high. I removed every bit of supporting structure at the bottom, and even cleared out 3 blocks high of materials. This smokestack is now floating in mid air but refuses to collapse. What am I missing? Is this a bug?

Here is a link to the images for review.

https://postimg.cc/gallery/Sm7jwq3

 

[Deverezieaux]

This isn't the first time I've seen this, and I remember some streamers doing the same thing in older versions (it's fun to watch stuff collapse!) and being perplexed when the smokestack didn't fall. I vaguely recall certain props in older versions basically acting like they had infinite structural integrity. I don't recall exactly what was in or around those smokestacks in older versions but if there's a prop (light, barrel, metal pile, ladder) somewhere inside or abutting one of the blocks I don't think it will fall. I actually think I experimented with exactly this after seeing it happen on a stream.