Hello,
After some internal discussion, it was decided that blocking bosses is no longer against our Official Server Rules.
You can check all the changes we made right here: Official Servers - Terms of conduct, guidelines and procedures
Hope this helps 
Hello everyone,
We sincerely appreciate everyone’s honest feedback regarding this recent change.
After reading your replies, we understand that many of you are frustrated and wanted to offer some additional clarity regarding our thought process.
When a boss’s spawn point is blocked, we evaluate if action is necessary based on if the boss is unique with unique loot, if the boss has multiple spawn points, and if the specific boss is or is not required for certain Journey steps.
For bosses with multiple spawn points, please keep in that mind that some of these spawn points are already protected from any building done by players, so blocking alternative spawn points for these bosses is no longer a rules infraction in and of itself.
Please be assured that we still review and investigate every report we receive on a case-by-case basis, and take into account any additional points of interest which may be blocked, the area it’s occupying, and any other building rules which may be applicable.
I hope that this information helps you to understand our reasoning a little better. We will, of course, be continuing to monitor player feedback regarding this change so that we can continue to support the community to the best of our ability.
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