You just have to do the math. My office with its 11m² has almost 2 kW cooling load ...
I’ll repeat the question of how this calculation works. Is that something realistic or more like a heat load calculation that represents extreme situations?
This is a practical cooling load calculation. It was therefore not assumed that the 4 m² of windows facing south are permanently unshaded. Without any windows, it would have been closer to 1 kW, but this should be mainly practical.