My eraser tool is all pixelated when i use a soft round brush... ANY HELP PLZ

I can replicate. It seems like kind of a bug. If you create layer beneath and fill it with white, noise or anomalies (pixelation) will dissapear right? Like on your last screenshot, if you have layer beneath or layer is a background layer pixelation will not show up, if you have normal layer filled with black color painting with Eraser will display noisy or pixelated edges.

Here are the screenshots, and no blend mode was applied.

Is there any blend mode beside Normal applied to layer? Can you post screenshot with Layers panel expanded and visible? It will be also useful to see WIndow > Brush Settings panel.