Are Texture2D Params Textures really loaded, if they are not used?

In this newly uploaded Talk (https://youtu.be/0SwlwgV-cz8?t=287) about how to resolve bottlenecks, the speaker says that textures in a master material are loaded even if the material instances override the texture parameter with their own textures. I wanted to know, if this is true, since 1) I couldn’t find anything about that in the Unreal Docs and 2) at the very least it doesn’t seem to be send to the graphics card for rendering (judging by disecting a frame in renderdoc, where the scene has both a standard material with a texture and a deferred decal with a texture).

afaict its actually true.
This is also why you should not use a master material as something you apply to an actor but only its instances.
just clean the texture object parameter and texture sample parameter nodes before saving the master material. (or use a tiny replacement texture)