To understand this, you need to have a comprehensive understanding of how a transformer works. Here is a typical transformer model with a magnetizing inductance in parallel with an ideal transformer, along with leakage inductance in primary. The ×-device is quite unique; without L and Leak, it models the ideal transformer (i.e., the turn ratio and voltage/current relationship). However, this type of transformer does not physically exist because a transformer is constructed with a coupled inductors. Therefore, it must have inductance, which includes magnetizing inductance and leakage inductance. If you solely use the ×-device with L and LEAK, everything is combined, making it somewhat challenging to analyze.
In my example, I have used the ×-device with Lm (green) and L1 as leakage (red). In below simulation with a leakage of 0.2uH, which is significant enough to restrict di/dt (rate of change of primary current). As di/dt is limited, the current cannot instantly shift from negative to positive during switching actions. The voltage drop across the ideal transformer is nearly zero during this di/dt-limited period by leakage, hence you won’t observe significant coupling into the secondary during this time, which is coupled through that ideal transformer in the model.
You can try gradually increasing the leakage value and observe the effects from the schematic I provided in the previous post. This may help you grasp what is happening.
