The reason structures and upgrades aren’t made in the physical realm is because the ingenuity is squelched in connecting with the other worlds. It seems that you can’t have upgrades in one world without having them happen in the other worlds as well. So the fact that so many negate the astral worlds as real, makes them irrelevant to the physical realm. Which, in turn prevents the physical realm from upgrading. Our imagination, creativity and expansiveness is so important to breathing vitality into the other realms. This solidifies their very existence. That is how empowered we are as dynamic omniscient beings.