You are calculating the energy of the building when it finally reaches the ground. But during the fall, there is no energy lost.

Energy is never lost ya ding dong. Unless you think conservation of energy is a hoax too that is.

All energy goes into the kinetic energy, the acceleration. This is what you missed in your calculation.

Haha, no I did not miss the kinetic energy. Re-read my last reply. It is clearly stated that all gravitational potential energy is converted to kinetic energy during the collapse. I am not sure you have done enough reading on how kinetic energy would be dissipated is such a situation (or in general for that matter).

You need the energy of the dynamics of the fall.

You might be referring to the turbulence of the falling objects. This is typically manifested as a dissipation of rotational kinetic energy as members spin around and bang into each other. Again, I clearly did not miss this.

The architects and engineers do know. Just check their website. The link I provided above explains it very clearly, much better than me.

You did not provide a link. I am sure architects and engineers (again, I am an engineer) could describe this better than you can though.

You need to be more wary of confirmation bias. Everything else you just said is irrelevant or nonsensical.