I am utterly appalled by this decision and declaration.
It is either to save facade in a dishonest way, or the result of a tremendously flawed logic.
As mentioned by others, if it is considered okay to block world bosses, then it is possible for all world bosses to be blocked. The only exceptions are the few instances of World Bosses inside dungeons or other non-constructible areas, but the options are very limited compared to what can be found in the world:
⢠Wine Cellar ā Demon Spider
⢠Weaverās Hollow ā Demon Spider
⢠Warmaker Dungeon ā Undead Dragon
⢠Arena ā Giant Snake
⢠Unnamed City ā Giant Snake
⢠Skittering Cavern ā The End of All Hope (Giant Spider, and unique content anyway)
⢠Abandoned Silver Mine ā King and Queen Scoprion
⢠Kingās Niche ā The Tortured King (who only spawns once every decade because he is bugged.)
⢠Circle of Swords ā Rotbranch
⢠Bin Yakinās Seal ā Feast on Flesh (unique content anyway)
⢠Lockstone Cave ā Shrouded by Darkness (unique content anyway)
I havenāt checked everything because really itās a pain and I have better things to do.
If you will notice, I couldnāt fingd a Giant Crocodile that cannot be built over; similarly, the Sand-Reaper Hive Queens can be built over except the one next to the Passage, but you can build close enough to prevent it from spawningā¦
Now onto the next question, the real question.
What if I want to fight Rockslide but itās been built over? Is it okay because it is a world boss, or is it not okay because it is a unique entity?
Same thing with the Reptilian Monstrosity (which is a world boss that drops a key, but is still labeled as 1-Skull by the way) as it is unique?
What if I want to fight Thunderfoot as well? Is it unique or is it just a world boss?
And then, what if every Giant Crocodile has been built over, but I specifically want to have a fight with this kind of entity?
I also checked, and it is possible to build around the spawn point of The Emissary of Atlach-Nacha in the volcano⦠I suppose you cannot block this spawn point because it is unique, despite being a 1-Skull Miniboss spawn.
Now letās say that hypothetically a second spawn point was added for the Emissary of Atlach-Nacha, the content would not be unique anymore, so it would become okay to block those spawn points (and both of them at once of course) 
Also, again hypothetically, what if I blocked every Blood Crystal spawn point (which isnāt technically possible, since there are some in non-buildable areas, but still consider the argument).
It would most likely be fine since all the resources granted by blood crystal spawns are accessible in different ways!
You can go inside Kurakās Lair to farm Blood Crystals (which requires Blood Crystals to enter of course, so you better have some already) and you can also collect random golem parts from sorcerers to build a golem then let it die then harvest its corpse.
So, hypothetically, it would be fine to block every single spawn points for Blood Crystal, at least per the same logic that permits blocking World Bosses.
Just to conclude, I also have to say that this does not affect me personally as I do not play on Official Servers. I mostly play Single-Player, so why do I even care about the world bosses in officials?
Itās not a question of personal gain/loss, it is about truth and logic.
And the truth that comes with your statement is that Funcom is hypocritical about their own rules.
Edit:
Well Iām very sorry to say this, but if internal discussion has led to this decision, either there is a terrible tyrant enforcing the worst possible decisions on your whole group, or the group as a whole it terrible in making those decisions⦠It genuinely seems impossible to me to arrive at your conclusion if a tiny bit of logic is applied. 