I work for a plastic recycling plant manufacturer, specifically for the sorting, shredding, cleaning and drying steps of plastic recycling (after that you usually have melting and extrusion before ending up with small plastic pellets that can be used to make other stuff).
I can confirm you, we have “cycling filtered grey water” cleaning. You don’t need to clean up your plastic containers, just empty them. Also various chemicals will be used in the process, when necessary.
We also make de-labelers to remove the labels from plastic bottles, although this kind of label in the picture is extremely hard to remove and, afaik, either requires human labor (aka poor countries with labor conditions you don’t want to think about) or just becomes waste. So yeah, this is some of the worst shit.