Ghost ids are limited to 17 bits. That means you can 2^17 or 131 072 ghosted objects. The first 2048 ghost ids are reserved for datablocks which means you can only have 129,024 objects in the world. That includes everything: bricks, players, lights, emitters, terrain, projectiles, vehicles, the sky, interiors - everything that exists in the world and can be updated.
If you have more than 129,024 total ghostable objects then new objects will not appear because they cannot be ghosted over to your client. New bricks will be invisible and you will not be able to shoot or respawn. Anyone who says they had an actual working build with much more than 128k bricks is mistaken.