The crossroads allowed access to the infinite dimensions but in terms of force its still very impressive in the fact that the concussive force had to travel across the crossroad dimensions AND ravaged those realities. They'd still have to strike with enough force not only to damage one dimension, but all of the others.
The idea that it would somehow dissipate equally makes little sense. Putting aside the very characteristics of a shock-wave, this is the crossroads:
The dimension doorways aren't neatly arranged an equal distance from the point of impact allowing equal distribution of force. It's a maze of doorways in a seemingly endless void. It's been a while so I forge the exact description of the crossroad dimension but hopefully my point comes across.
It's a feat with still a huge asterisk due to the location of the exchange but still way up there in power.
