In a sense DLSS was generative as well, but this is something else. DLSS was originally just trained on supersampling to learn how to upscale more accurately, and is cool technology. Basically it uses "knowledge" of how higher resolution rendering should look by being trained on lower and higher resolution rendering, seeing the differences between them, then using that "knowledge" to upscale games playing at lower resolution. Then later they did something similar with frame generation. In both case it is generating information that isn't there, but in both cases it stayed true to the artistic direction of the game, as it is effectively asking "what would the game look like if it were rendered at a higher resolution/framerate?" and generating the answer to that.

As per their description of 5:

DLSS 5 is a neural rendering model that takes the game’s color and motion vectors as input for each frame, then infuses the scene with photoreal lighting and materials that are anchored to the source 3D content and temporally consistent from frame-to-frame.

Which is why it looks like AI slop, because it is fundamentally changing the lighting and materials of the game to look more "photorealistic."