Using "Material Instance Dynamic" in "Set Scalar Parameter Value"

I have a simple issue here. I’m new to blueprint scripting and I’m following this tutorial: [link][1].

For some reason, when I create a “Set Scalar Parameter Value”, i can’t bind my Material Instance Dynamic as a target. But when I drag a line from the Material Instance Dynamic and then create the “Set Scalar Parameter Value”, it does link. Can anyone tell me why?

The one that you cannot connect is for Parameter Collections. It requires you to set a collection and parameter name. For more info on Parameter Collections:

Parameter collection doesnt need a material or material instance as a target so you can access it whenever you like(if you have checke the documentation parameter collection affects every material it is used in so it is global), whereas dynamic material instance is specific to material instance parameters, so you have to give it a dynamic mat. instance as a target in order to access the function.

But why does it behave this way? Why doesn’t it connect if you bind it later on?